United States Department of Defense - Wikipedia United States Department of Defense United States Department of Defense Department overview Formed September 18, 1947 ; 70 years ago ( 1947 - 09 - 18 ) ( as National Military Establishment ) Preceding Department U.S. Department of the Army U.S. Department of the Navy U.S. Department of the Air Force Type Executive Department Headquarters The Pentagon Arlington County, Virginia, United States 38 ° 52 ′ 16 '' N 77 ° 3 ′ 21 '' W ﻿ / ﻿ 38.87111 ° N 77.05583 ° W ﻿ / 38.87111 ; - 77.05583 Coordinates : 38 ° 52 ′ 16 '' N 77 ° 3 ′ 21 '' W ﻿ / ﻿ 38.87111 ° N 77.05583 ° W ﻿ / 38.87111 ; - 77.05583 Employees 742,000 ( civilian ) 1,300,000 ( active duty military ) 826,000 ( National Guard and reserve ) : 2.87 million total ( 2016 ) Annual budget US $530.1 billion ( 2010 ) US $549.1 billion ( 2011 ) US $553.0 billion ( est. 2012 ) US $496.1 billion ( 2015 ) US $534.3 billion ( base FY2016 ) Department executives Jim Mattis, Secretary Patrick M. Shanahan, Deputy Secretary Child agencies U.S. Department of the Army U.S. Department of the Navy U.S. Department of the Air Force Website www.defense.gov The Pentagon, headquarters of the U.S. Department of Defense The Department of Defense ( DoD, USDOD, or DOD ) is an executive branch department of the federal government of the United States charged with coordinating and supervising all agencies and functions of the government concerned directly with national security and the United States Armed Forces. The Department is the largest employer in the world, with nearly 1.3 million active duty servicemen and women as of 2016. Adding to its employees are over 826,000 National Guardsmen and Reservists from the four services, and over 742,000 civilians bringing the total to over 2.8 million employees. It is headquartered at the Pentagon in Arlington, Virginia, just outside Washington, D.C. The Department of Defense is headed by the Secretary of Defense, a cabinet - level head who reports directly to the President of the United States. Beneath the Department of Defense are three subordinate military departments : the United States Department of the Army, the United States Department of the Navy, and the United States Department of the Air Force. In addition, four national intelligence services are subordinate to the Department of Defense : the Defense Intelligence Agency ( DIA ), the National Security Agency ( NSA ), the National Geospatial - Intelligence Agency ( NGA ), and the National Reconnaissance Office ( NRO ). Other Defense Agencies include the Defense Advanced Research Projects Agency ( DARPA ), the Defense Logistics Agency ( DLA ), the Missile Defense Agency ( MDA ), the Defense Health Agency ( DHA ), Defense Threat Reduction Agency ( DTRA ), the Defense Security Service ( DSS ), and the Pentagon Force Protection Agency ( PFPA ), all of which are under the command of the Secretary of Defense. Military operations are managed by nine regional or functional Unified combatant commands. The Department of Defense also operates several joint services schools, including the National Defense University ( NDU ) and the National War College ( NWC ). Contents 1 History 1.1 The War Department 1.2 National Military Establishment 2 Organizational structure 2.1 Office of the Secretary of Defense 2.1. 1 Defense Agencies 2.1. 2 National Intelligence Agencies 2.2 Joint Chiefs of Staff 2.3 Military Departments 2.4 Unified Combatant Commands 3 Budget 4 Criticism 4.1 2016 Internal Study Cover Up 4.2 Manipulation of Finances 5 Energy use 6 Freedom of Information Act processing performance 7 Related legislation 8 See also 9 Notes 10 References 11 External links History See also : National Security Act of 1947 and History of the United States military The history of the defense of the United States started with the Continental Congress in 1775. The creation of the United States Army was enacted on June 14, 1775. This coincides with the American holiday Flag Day. The Second Continental Congress would charter the United States Navy, on October 13, 1775, and create the United States Marine Corps on November 10, 1775. Today, both the Navy and the Marine Corps are separate military services subordinate to the Department of the Navy. The War Department Main article : United States Department of War The Preamble of the United States Constitution gave the authority to the federal government to defend its citizens : We the People of the United States, in Order to form a more perfect Union, establish Justice, insure domestic Tranquility, provide for the common defence, promote the general Welfare, and secure the Blessings of Liberty to ourselves and our Posterity, do ordain and establish this Constitution for the United States of America. -- Constitution of the United States Upon the seating of the first Congress on March 4, 1789, legislation to create a military defense force stagnated as they focused on other concerns relevant to setting up the new government. President George Washington went to Congress to remind them of their duty to establish a military twice during this time. Finally, on the last day of the session, September 29, 1789, Congress created the War Department, historic forerunner of the Department of Defense. The War Department handled naval affairs until Congress created the Navy Department in 1798. The secretaries of each of these departments reported directly to the President as cabinet - level advisors until 1949, when all military departments became subordinate to the Secretary of Defense. National military Establishment President Harry Truman signs the National Security Act Amendment of 1949 After the end of World War II, President Harry Truman proposed creation of a unified department of national defense. In a special message to Congress on December 19, 1945, the President cited both wasteful military spending and inter-departmental conflicts. Deliberations in Congress went on for months focusing heavily on the role of the military in society and the threat of granting too much military power to the executive. On July 26, 1947, Truman signed the National Security Act of 1947, which set up a unified military command known as the `` National Military Establishment '', as well as creating the Central Intelligence Agency, the National Security Council, National Security Resources Board, United States Air Force ( formerly the Army Air Forces ) and the Joint Chiefs of Staff. The act placed the National Military Establishment under the control of a single Secretary of Defense. The National Military Establishment formally began operations on September 18, the day after the Senate confirmed James V. Forrestal as the first Secretary of Defense. The National Military Establishment was renamed the `` Department of Defense '' on August 10, 1949 and absorbed the three cabinet level military departments, in an amendment to the original 1947 law. Under the Department of Defense Reorganization Act of 1958 ( Pub. L. 85 -- 599 ), channels of authority within the department were streamlined, while still maintaining the ordinary authority of the Military Departments to organize, train and equip their associated forces. The Act clarified the overall decision - making authority of the Secretary of Defense with respect to these subordinate Military Departments and more clearly defined the operational chain of command over U.S. military forces ( created by the military departments ) as running from the President to the Secretary of Defense and then to the unified combatant commanders. Also provided in this legislation was a centralized research authority, the Advanced Research Projects Agency, eventually known as DARPA. The act was written and promoted by the Eisenhower administration, and was signed into law August 6, 1958. Organizational structure Main article : Organizational structure of the United States Department of Defense See also : List of Department of Defense agencies Department of Defense organizational chart ( December 2013 ) The Secretary of Defense, appointed by the President with the advice and consent of the Senate, is by federal law ( 10 U.S.C. § 113 ) the head of the Department of Defense, `` the principal assistant to the President in all matters relating to Department of Defense '', and has `` authority, direction and control over the Department of Defense ''. Because the Constitution vests all military authority in Congress and the President, the statutory authority of the Secretary of Defense is derived from their constitutional authorities. Since it is impractical for either Congress or the President to participate in every piece of Department of Defense affairs, the Secretary of Defense, and the Secretary 's subordinate officials generally exercise military authority. The Department of Defense is composed of the Office of the Secretary of Defense ( OSD ), the Joint Chiefs of Staff ( JCS ) and the Joint Staff ( JS ), Office of the Inspector General ( DODIG ), the Combatant Commands, the Military Departments ( Department of the Army ( DA ), Department of the Navy ( DON ) & Department of the Air Force ( DAF ) ), the Defense Agencies and Department of Defense Field Activities, the National Guard Bureau ( NGB ), and such other offices, agencies, activities, organizations, and commands established or designated by law, or by the President or by the Secretary of Defense. Department of Defense Directive 5100.01 describes the organizational relationships within the Department, and is the foundational issuance for delineating the major functions of the Department. The latest version, signed by former Secretary of Defense Robert Gates in December 2010, is the first major re-write since 1987. Office of the Secretary of Defense Main article : Office of the Secretary of Defense 2008 OSD organizational chart The Office of the Secretary of Defense ( OSD ) is the Secretary and Deputy Secretary 's ( mainly ) civilian staff. OSD is the principal staff element of the Secretary of Defense in the exercise of policy development, planning, resource management, fiscal and program evaluation and oversight, and interface and exchange with other U.S. Government departments and agencies, foreign governments, and international organizations, through formal and informal processes. OSD also performs oversight and management of the Defense Agencies and Department of Defense Field Activities. Defense agencies OSD also supervises the following Defense Agencies : Armed Forces Radiobiology Research Institute ( AFRRI ) Department of Defense Education Activity ( DoDEA ) Defense Advanced Research Projects Agency ( DARPA ) Defense Commissary Agency ( DeCA ) Defense Contract Audit Agency ( DCAA ) Defense Contract Management Agency ( DCMA ) Defense Finance and Accounting Service ( DFAS ) Defense Information Systems Agency ( DISA ) Defense Legal Services Agency Defense Logistics Agency ( DLA ) Defense Security Cooperation Agency ( DSCA ) ( formerly Defense Security Assistance Agency ) Defense Security Service ( DSS ) ( formerly Defense Investigative Service ) Defense Technical Information Center ( DTIC ) Defense Threat Reduction Agency ( DTRA ) Missile Defense Agency ( MDA ) National intelligence agencies Several defense agencies are members of the United States Intelligence Community. These are national - level intelligence services that operate under the jurisdiction of the Department of Defense but simultaneously fall under the authorities of the Director of National Intelligence. They fulfill the requirements of national policy makers and war planners, serve as Combat Support Agencies, and also assist non-Department of Defense intelligence or law enforcement services such as the Central Intelligence Agency and the Federal Bureau of Investigation. The military services each have their own intelligence elements which are distinct from but subject to coordination, by national intelligence agencies under Department of Defense. Department of Defense manages the nation 's coordinating authorities and assets in disciplines of signals intelligence, geospatial intelligence, and measurement and signature intelligence, and also builds, launches and operates the Intelligence Community 's satellite assets. Department of Defense also has its own human intelligence service, which contributes to the CIA 's human intelligence efforts while also focusing on military human intelligence priorities. These agencies are directly overseen by the Undersecretary of Defense for Intelligence. National Intelligence Agencies under the Department of Defense Defense Intelligence Agency National Security Agency National Geospatial - Intelligence Agency National Reconnaissance Office Joint Chiefs of Staff Main article : Joint Chiefs of Staff Joint Chiefs of Staff / Joint Staff organizational chart. The Joint Chiefs of Staff ( JCS ) is a body of senior uniformed leaders in the Department of Defense who advise the Secretary of Defense, the Homeland Security Council, the National Security Council and the President on military matters. The composition of the Joint Chiefs of Staff is defined by statute and consists of the Chairman of the Joint Chiefs of Staff ( CJCS ), Vice Chairman of the Joint Chiefs of Staff ( VCJCS ), Senior Enlisted Advisor to the chairman ( SEAC ), the Military Service Chiefs from the Army, Marine Corps, Navy, and Air Force, in addition to the Chief of National Guard Bureau, all appointed by the President following Senate confirmation. Each of the individual Military Service Chiefs, outside their Joint Chiefs of Staff obligations, works directly for the Secretary of the Military Department concerned, i.e. Secretary of the Army, Secretary of the Navy, and the Secretary of the Air Force. Following the Goldwater - Nichols Act in 1986 the Joint Chiefs of Staff do not have operational command authority, neither individually nor collectively, as the chain of command goes from the President to the Secretary of Defense, and from the Secretary of Defense to the Commanders of the Combatant Commands. Goldwater - Nichols also created the office of vice-chairman, and the chairman is now designated as the principal military adviser to the Secretary of Defense, the Homeland Security Council, the National Security Council and to the President. The Joint Staff ( JS ) is a headquarters staff at the Pentagon composed of personnel from all four services that assist the chairman and vice-chairman in discharging their duties, and managed by the Director of the Joint Staff ( DJS ) who is a Lieutenant General or Vice Admiral. Military Departments Military Departments of the Department of Defense Department of the Army Department of the Navy Department of the Air Force There are three Military Departments within the Department of Defense : the Department of the Army, which the United States Army is organized within. the Department of the Navy, which the United States Navy and the United States Marine Corps are organized within. the Department of the Air Force, which the United States Air Force is organized within. The Military Departments are each headed by their own Secretary ( i.e., Secretary of the Army, Secretary of the Navy and Secretary of the Air Force ), appointed by the President, with the advice and consent of the Senate. They have legal authority under Title 10 of the United States Code to conduct all the affairs of their respective departments within which the military services are organized. The Secretaries of the Military Departments are ( by law ) subordinate to the Secretary of Defense and ( by SecDef delegation ) to the Deputy Secretary of Defense. The Secretaries of the Military Departments, in turn, normally exercises authority over their forces by delegation through their respective Service Chiefs ( i.e., Chief of Staff of the Army, Commandant of the Marine Corps, Chief of Naval Operations, and Chief of Staff of the Air Force ) over forces not assigned to a Combatant Command. The Secretaries of the Military Departments and the Service Chiefs do not possess operational command authority over U.S. troops ( this power was stripped from them in the Defense Reorganization Act of 1958 ), and instead the Military Departments are tasked solely with `` the training, provision of equipment, and administration of troops. '' Unified Combatant Commands Map of the Department of Defense 's geographic commands A Unified Combatant Command is a military command composed of personnel and equipment from at least two Military Departments, which has a broad and continuing mission. The Military Departments are responsible for equipping and training the troops to fight, while the Unified Combatant Commands are responsible for actual operational command of military forces. Almost all operational U.S. forces are under the authority of a Unified Command. The Unified Commands are governed by a Unified Command Plan, a frequently updated document ( produced by the Department of Defense ) which lays out the Command 's mission, geographical / functional responsibilities, and force structure. During military operations, the chain of command runs from the President to the Secretary of Defense to the combatant commanders of the Combatant Commands. The United States currently has nine Combatant Commands, organized either on a geographical basis ( known as `` area of responsibility '', AOR ) or on a global, functional basis : U.S. Northern Command ( USNORTHCOM ) U.S. Southern Command ( USSOUTHCOM ) U.S. Central Command ( USCENTCOM ) U.S. European Command ( USEUCOM ) U.S. Pacific Command ( USPACOM ) U.S. Africa Command ( USAFRICOM ) U.S. Strategic Command ( USSTRATCOM ) U.S. Special Operations Command ( USSOCOM ) U.S. Transportation Command ( USTRANSCOM ) Budget Chart showing growth in U.S. Department of Defense spending 2000 -- 2011 Main article : Military budget of the United States Department of Defense spending in 2010 was 4.8 % of GDP and accounted for about 45 % of budgeted global military spending -- more than the next 17 largest militaries combined. The Department of Defense accounts for the majority of federal discretionary spending. In FY 2010 the Department of Defense budgeted spending accounted for 21 % of the U.S. Federal Budget, and 53 % of federal discretionary spending, which represents funds not accounted for by pre-existing obligations. However, this does not include many military - related items that are outside the Defense Department budget, such as nuclear weapons research, maintenance, cleanup, and production, which is in the Department of Energy budget, Veterans Affairs, the Treasury Department 's payments in pensions to military retirees and widows and their families, interest on debt incurred in past wars, or State Department financing of foreign arms sales and militarily - related development assistance. Neither does it include defense spending that is not military in nature, such as the Department of Homeland Security, counter-terrorism spending by the FBI, and intelligence - gathering spending by the NSA. In the 2010 United States federal budget, the Department of Defense was allocated a base budget of $533.7 billion, with a further $75.5 billion adjustment in respect of 2009, and $130 billion for overseas contingencies. The subsequent 2010 Department of Defense Financial Report shows the total budgetary resources for fiscal year 2010 were $1.2 trillion. Of these resources, $1.1 trillion were obligated and $994 billion were disbursed, with the remaining resources relating to multi-year modernization projects requiring additional time to procure. After over a decade of non-compliance, Congress has established a deadline of Fiscal year 2017 for the Department of Defense to achieve audit readiness. In 2015 the allocation for the Department of Defense was $585 billion, the highest level of budgetary resources among all Federal agencies, and this amounts to more than one - half of the annual Federal Expenditures in the United States federal budget discretionary budget. Criticism 2016 internal study cover up In 2015, a Pentagon consulting firm performed an audit on the department of defense 's budget. It found that there was $125 billion in wasteful spend that could be saved over the next 5 years without layoffs or reduction in military personnel. In 2016, The Washington Post uncovered that rather than taking the advise of the auditing firm, senior defense officials suppressed and hid the report from the public to avoid political scrutiny. Manipulation of finances In June 2016, The Defense Department 's Inspector General released a report that stated the United States Army made $6.5 trillion in wrongful adjustments to its accounting entries in 2015. Energy use Main article : Energy usage of the United States military The Department of Defense was the largest single consumer of energy in the United States in 2006. In FY 2006, the Department used almost 30,000 gigawatt hours ( GWH ) of electricity, at a cost of almost $2.2 billion. The Department 's electricity use would supply enough electricity to power more than 2.6 million average American homes. In electricity consumption, if it were a country, the Department would rank 58th in the world, using slightly less than Denmark and slightly more than Syria ( CIA World Factbook, 2006 ). The Department of Defense is responsible for 93 % of all US government fuel consumption in 2007 ( Department of the Air Force : 52 % ; Department of the Navy : 33 % ; Department of the Army : 7 % ; other Department components : 1 % ). The Department of Defense uses 4,600,000,000 US gallons ( 1.7 × 10 L ) of fuel annually, an average of 12,600,000 US gallons ( 48,000,000 L ) of fuel per day. A large Army division may use about 6,000 US gallons ( 23,000 L ) per day. According to the 2005 CIA World Factbook, if it were a country, the Department of Defense would rank 34th in the world in average daily oil use, coming in just behind Iraq and just ahead of Sweden. The Air Force is the largest user of fuel energy in the federal government. The Air Force uses 10 % of the nation 's aviation fuel. ( JP - 8 accounts for nearly 90 % of its fuels. ) This fuel usage breaks down as such : 82 % jet fuel, 16 % facility management and 2 % ground vehicle / equipment. Freedom of Information Act processing performance In the latest Center for Effective Government analysis of 15 federal agencies which receive the most Freedom of Information Act ( United States ) ( FOIA ) requests, published in 2015 ( using 2012 and 2013 data, the most recent years available ), the DoD earned a D − by scoring 61 out of a possible 100 points, i.e. did not earn a satisfactory overall grade. While it had improved from a failing grade in 2013, it still had low scores in processing requests ( 55 % ) and their disclosure rules ( 42 % ). Related legislation The organization and functions of the Department of Defense are in Title 10 of the United States Code. Other significant legislation related to the Department of Defense includes : 1947 : National Security Act of 1947 1958 : Department of Defense Reorganization Act, Pub. L. 85 -- 899 ( see note in history section above ) 1963 : Department of Defense Appropriations Act, Pub. L. 88 -- 149 1963 : Military Construction Authorization Act, Pub. L. 88 -- 174 1967 : Supplemental Defense Appropriations Act, Pub. L. 90 -- 8 1984 : Department of Defense Authorization Act, Pub. L. 98 -- 525 1986 : Goldwater - Nichols Act of 1986 ( Department of Defense Reorganization Act ), Pub. L. 99 -- 433 1996 : Antiterrorism and Effective Death Penalty Act, Pub. L. 104 -- 132 See also Government of the United States portal Military history portal Arms industry List of United States military bases Military -- industrial complex Nuclear weapons Private military company Title 32 of the Code of Federal Regulations United States Department of Homeland Security United States Department of Justice United States Department of Veterans Affairs Warrior Games Notes Jump up ^ soldiers, marines, sailors, airmen Jump up ^ Army, Marine Corps, Navy, and Air Force References ^ Jump up to : `` About Department of Defense ''. U.S. Department of Defense. Retrieved July 17, 2017. Jump up ^ `` Budget of the US Government, FY 2011 '' ( PDF ). Archived from the original ( PDF ) on 17 February 2011. Retrieved 15 October 2010. Jump up ^ `` Defense.gov '' ( PDF ). Archived from the original ( PDF ) on 17 February 2011. ^ Jump up to : `` United States Department of Defense Fiscal Year 2016 Budget Request / Overview '' ( PDF ). Office of the Under Secretary of Defense ( Comptroller ) Chief Financial Officer. February 2015. Retrieved August 20, 2015. Jump up ^ `` Manual for Written Material '' ( PDF ). Department of Defense. p. 9. Archived from the original ( PDF ) on August 29, 2004. Retrieved December 10, 2014. Jump up ^ `` The World 's Biggest Employers ''. Forbes.com. Forbes. Retrieved July 31, 2015. Jump up ^ `` Department of Defense ( DoD ) Releases Fiscal Year 2017 President 's Budget Proposal ''. U.S. Department of Defense. February 9, 2016. Retrieved February 11, 2016. Jump up ^ Maass, John R. ( June 14, 2012 ). `` June 14th : The Birthday of the U.S. Army ''. U.S. Army Center of Military History. Retrieved June 19, 2014. Jump up ^ Naval History and Heritage Command. `` Navy Birthday Information -- 13 October 1775 ''. Retrieved June 19, 2014. Jump up ^ `` Marine Corps : Timeline ''. United States Marine Corps. Retrieved June 19, 2014. Jump up ^ `` Congress Officially Created the U.S. Military : September 29, 1789 ''. Library of Congress. Retrieved June 20, 2014. Jump up ^ Joe Carmel, ed. ( n.d. ) ( Original Statute 1789 ). `` Statutes at Large, Session I, Charter XXV '' ( PDF ). Legisworks. Retrieved January 28, 2018. An Act to recognize and adapt to the Constitution of the United States the establishment of the Troops raised under the Resolves of the United Stales in Congress assembled, and for other purposes therein mentioned. Jump up ^ Hogan, Michael J. ( 2000 ). A cross of iron : Harry S. Truman and the origins of the national security state, 1945 -- 1954. Cambridge University Press. pp. 37 -- 38. ISBN 978 - 0 - 521 - 79537 - 1. Jump up ^ Polmar, Norman ( 2005 ). The Naval Institute guide to the ships and aircraft of the U.S. fleet. Naval Institute Press. p. 17. ISBN 978 - 1 - 59114 - 685 - 8. ^ Jump up to : `` James V. Forrestal, Harry S. Truman Administration ''. Historical Office, Office of the Secretary of Defense. Office of the Secretary of Defense. Retrieved July 25, 2017. Jump up ^ Bolton, M. Kent ( 2008 ). U.S. national security and foreign policymaking after 9 / 11 : present at the re-creation. Rowman & Littlefield. p. 3. ISBN 978 - 0 - 7425 - 5900 - 4. Jump up ^ Rearden, Steven L. ( 2001 ). `` Department of Defense ''. In DeConde, Alexander et al. Encyclopedia of American Foreign Policy, Volume 1. Simon and Schuster. ISBN 978 - 0 - 684 - 80657 - 0. CS1 maint : Uses editors parameter ( link ) Jump up ^ `` Organizational and Management Planning ''. Odam.defense.gov. Retrieved 2013 - 06 - 15. Jump up ^ Department of Defense Directive 5100.01 Jump up ^ ( 1 ) 10 USC 151. Joint Chiefs of Staff : composition ; functions Jump up ^ 10 U.S.C. § 3033 Archived March 12, 2013, at the Wayback Machine. Jump up ^ 10 U.S.C. § 5033 Archived March 12, 2013, at the Wayback Machine. Jump up ^ 10 U.S.C. § 5043 Archived March 12, 2013, at the Wayback Machine. Jump up ^ 10 U.S.C. § 8033 Archived March 12, 2013, at the Wayback Machine. Jump up ^ 10 U.S.C. § 162 ( b ) Archived May 29, 2013, at the Wayback Machine. Jump up ^ 10 U.S.C § 151 ( b ) Archived March 12, 2013, at the Wayback Machine. Jump up ^ 10 U.S.C § 155 Archived March 12, 2013, at the Wayback Machine. Jump up ^ Polmar, Norman ( 2005 ). `` Defense organization ''. The Naval Institute guide to the ships and aircraft of the U.S. fleet. Naval Institute Press. ISBN 978 - 1 - 59114 - 685 - 8. Jump up ^ 10 U.S.C. § 3013, 10 U.S.C. § 5013 and 10 U.S.C. § 8013 ^ Jump up to : Polmar, Norman ( 2005 ). `` Defense Organization ''. The Naval Institute guide to the ships and aircraft of the U.S. fleet. Naval Institute Press. p. 20. ISBN 978 - 1 - 59114 - 685 - 8. Jump up ^ Watson, Cynthia A. ( 2010 ). Combatant Commands : Origins, Structure, and Engagements. ABC - CLIO. p. 3. ISBN 978 - 0 - 313 - 35432 - 8. ^ Jump up to : Whitley, Joe D. ; et al., eds. ( 2009 ). `` Unified Combatant Commands and USNORTHCOM ''. Homeland security : legal and policy issues. American Bar Association. ISBN 978 - 1 - 60442 - 462 - 1. Jump up ^ Reveron, Derek S. ( 2007 ). America 's Viceroys : The Military and U.S. Foreign Policy. Macmillan. p. 26. ISBN 978 - 0 - 230 - 60219 - 9. Jump up ^ `` Military Spending : Defence Costs ''. The Economist. June 8, 2011. Jump up ^ `` The SIPRI Military Expenditure Database ''. Stockholm International Peace Research Institute. Archived from the original on 28 March 2010. Retrieved 13 December 2011. Jump up ^ `` United States Federal Budget for Fiscal Year 2010 '' ( PDF ). Government Printing Office. Archived from the original ( PDF ) on 5 February 2011. Retrieved 9 January 2010. Jump up ^ `` United States Federal Budget for Fiscal Year 2010 ( vid. p. 53 ) '' ( PDF ). Government Printing Office. Archived from the original ( PDF ) on 5 February 2011. Retrieved 9 January 2010. ^ Jump up to : `` FY 2010 DoD Agencywide Agency Financial Report ( vid. p. 25 ) '' ( PDF ). US Department of Defense. Retrieved January 7, 2011. Jump up ^ `` Financial Improvement and Audit Readiness ( FIAR ) Plan Status Report '' ( PDF ). Comptroller, Department of Defense. Retrieved September 16, 2016. Jump up ^ `` Current & Future Defense Capabilities of the U.S ''. UTEP. Retrieved August 18, 2015. Jump up ^ `` Federal Spending : Where Does the Money Go ''. National Priorities Project. Retrieved August 18, 2015. Jump up ^ Whitlock, Craig ; Woodward, Bob ( 2016 - 12 - 05 ). `` Pentagon buries evidence of $125 billion in bureaucratic waste ''. Washington Post. ISSN 0190 - 8286. Retrieved 2017 - 12 - 18. Jump up ^ `` U.S. Army fudged its accounts by trillions of dollars, auditor finds ''. Reuters. 19 August 2016. Retrieved 2017 - 12 - 18. Jump up ^ Andrews Anthony ( 2011 ). Department of Defense Facilities : Energy Conservation Policies and Spending. DIANE Publishing. p. 1. ISBN 978 - 1 - 4379 - 3835 - 7. ^ Jump up to : Colonel Gregory J. Lengyel, USAF, The Brookings Institution, Department of Defense Energy Strategy, August 2007. Jump up ^ Colonel Gregory J. Lengyel, USAF, The Brookings Institution, Department of Defense Energy Strategy, August 2007, `` Archived copy '' ( PDF ). Archived from the original ( PDF ) on 26 July 2010. Retrieved 12 September 2009. Jump up ^ Powering America 's Defense : Energy and the Risks to National Security, CNA Analysis & Solutions, May 2009 Jump up ^ Making the Grade : Access to Information Scorecard 2015 March 2015, 80 pages, Center for Effective Government, retrieved March 21, 2016 External links Wikimedia Commons has media related to United States Department of Defense and The Pentagon. Official website Department of Defense in the Federal Register Office of the Under Secretary of Defense ( Comptroller ) Budget and Financial Management Policy Death and Taxes : 2009 -- A visual guide and infographic of the 2009 United States federal budget including the Department of Defense with data provided by the Comptrollers office. Department of Defense IA Policy Chart Works by United States Department of Defense at Project Gutenberg Works by or about United States Department of Defense at Internet Archive Department of Defense Collection on the Internet Archive United States Department of Defense Headquarters : The Pentagon James Mattis, Secretary of Defense Patrick M. Shanahan, Deputy Secretary of Defense Office of the Secretary of Defense ( including Defense Agencies and DoD Field Activities ) Deputy Secretary of Defense Deputy 's Advisory Working Group Office of Net Assessment Special Access Program Oversight Committee Under Secretary of Defense for Acquisition, Technology and Logistics Director, Defense Research and Engineering Defense Advanced Research Projects Agency Missile Defense Agency Defense Contract Management Agency Defense Logistics Agency Defense Technical Information Center Defense Threat Reduction Agency Office of Economic Adjustment Defense Acquisition University Defense Acquisition Board Under Secretary of Defense for Policy Defense Security Cooperation Agency Defense POW / MIA Accounting Agency Defense Policy Board Advisory Committee Under Secretary of Defense ( Comptroller ) Defense Contract Audit Agency Defense Finance and Accounting Service Under Secretary of Defense for Personnel and Readiness Defense Commissary Agency Department of Defense Education Activity DoD Human Resources Activity Military Health System Uniformed Services University of the Health Sciences Defense Equal Opportunity Management Institute Under Secretary of Defense for Intelligence Defense Intelligence Agency Defense Security Service Defense Information Systems Agency National Geospatial - Intelligence Agency National Reconnaissance Office National Security Agency ( Director ) Assistant Secretary of Defense for Public Affairs Defense Media Activity ( American Forces Press Service, American Forces Radio and Television Service, Stars and Stripes, The Pentagon Channel ) General Counsel of the Department of Defense Defense Legal Services Agency Director of Administration and Management Pentagon Force Protection Agency Washington Headquarters Services Military Departments Department of the Army Secretary of the Army The Secretariat : Under Secretary of the Army Assistant Secretary for Acquisition, Logistics, and Technology Assistant Secretary for Civil Works Assistant Secretary ( Financial Management and Comptroller ) Assistant Secretary of the Army for Installations, Energy and Environment Assistant Secretary of the Army for Manpower and Reserve Affairs General Counsel of the Army The Administrative Assistant The Army Staff : Chief of Staff of the Army Vice Chief of Staff of the Army Sergeant Major of the Army Deputy Chief of Staff G - 8 Chief of Chaplains Judge Advocate General Provost Marshal General Surgeon General U.S. Army field organizations : see Structure of the United States Army Department of the Navy Secretary of the Navy The Secretariat : Under Secretary of the Navy Assistant Secretary of the Navy ( Financial Management and Comptroller ) Assistant Secretary of the Navy ( Installations and Environment ) Assistant Secretary of the Navy ( Manpower and Reserve Affairs ) Assistant Secretary of the Navy ( Research, Development and Acquisitions ) General Counsel of the Navy Judge Advocate General Naval Criminal Investigative Service Naval Inspector General Headquarters Marine Corps : Commandant of the Marine Corps Assistant Commandant of the Marine Corps Sergeant Major of the Marine Corps Chaplain U.S. Marine Corps field organizations : see Organization of the United States Marine Corps Office of the Chief of Naval Operations : Chief of Naval Operations Vice Chief of Naval Operations Master Chief Petty Officer of the Navy Director of Naval Reactors Chief of Chaplains Chief of Naval Personnel Surgeon General United States Navy field organizations : see Structure of the United States Navy Department of the Air Force Secretary of the Air Force The Secretariat : Under Secretary of the Air Force Assistant Secretary of the Air Force ( Acquisition ) Assistant Secretary of the Air Force ( Financial Management & Comptroller ) Assistant Secretary of the Air Force ( Installations, Environment & Logistics ) Assistant Secretary of the Air Force ( Manpower & Reserve Affairs ) General Counsel of the Air Force Air Force Office of Special Investigations The Air Staff : Chief of Staff of the Air Force Vice Chief of Staff of the Air Force Chief Master Sergeant of the Air Force Chief of Chaplains Chief of Safety Chief Scientist Judge Advocate General Surgeon General U.S. Air Force field organizations : Major Commands Direct Reporting Units Field Operating Agencies Joint Chiefs of Staff Chairman of the Joint Chiefs of Staff Vice Chairman of the Joint Chiefs of Staff Senior Enlisted Advisor to the Chairman Joint Requirements Oversight Council Director of the Joint Staff Joint Staff National Military Command Center Alternate National Military Command Center National Defense University Combatant Commands Africa Command Central Command European Command Northern Command Pacific Command Southern Command Special Operations Command Strategic Command ( Cyber Command ) Transportation Command National Guard Bureau Chief of the National Guard Bureau Air National Guard Army National Guard Office of the Inspector General Defense Criminal Investigative Service United States Armed Forces Book Portal MC AF CG MC AF CG Navbox MC AF CG Leadership Commander - in - chief : President of the United States Secretary of Defense Deputy Secretary of Defense Secretary of Homeland Security Deputy Secretary of Homeland Security Joint Chiefs of Staff : Chairman Vice Chairman United States Congress : Committees on Armed Services : Senate House Active duty four - star officers United States military seniority National Security Act of 1947 Goldwater -- Nichols Act Organization Service departments Department of Defense ( Secretary ) : Army ( Secretary ) Navy ( Secretary ) Air Force ( Secretary ) Department of Homeland Security ( Secretary ) : Coast Guard Branches Army ( Chief of Staff ) Marine Corps ( Commandant ) Navy ( Chief of Naval Operations ) Air Force ( Chief of Staff ) Coast Guard ( Commandant ) Reserve components Reserves : A MC N AF CG National Guard : A AF Civilian auxiliaries Military Auxiliary Radio System Merchant Marine Civil Air Patrol Coast Guard Auxiliary Unified Combatant Command Northern Central European Pacific Southern Africa Special Operations Strategic Transportation Structure United States Code Title 10 Title 14 Title 32 Title 50 The Pentagon Installations Units : A MC N AF CG Logistics Media Unit mottoes Operations and history Current deployments Conflicts Wars Timeline History : A MC N AF CG Colonial World War II Civil affairs African Americans Asian Americans Buddhist Americans Jewish Americans Muslim Americans Pakistani Americans Sikh Americans Historiography : Army Center of Military History MC History Division Naval History and Heritage Command Air Force Historical Research Agency American official war artists : Army Art Program AF Art Program Personnel Training MEPS ASVAB Recruit training : A MC N AF CG Officer candidate school : A MC N AF Warrant : A MC Service academies : A ( prep ) N ( prep ) AF ( prep ) CG Merchant Marine ROTC A : ECP MC / N AF Medical Other education Uniforms Uniforms : A MC N AF CG Awards & decorations : Inter-service A MC / N AF CG Foreign International Devices Badges : Identification A MC N AF CG Ranks Enlisted : A MC N AF CG Warrant officers Officer : A MC N AF CG Other Oath : Enlistment Office Creeds & Codes : Code of Conduct NCO A MC N AF CG Service numbers : A MC N AF CG Military Occupational Specialty / Rating / Air Force Specialty Code Pay Uniform Code of Military Justice Judge Advocate General 's Corps Military Health System / TRICARE Separation Veterans Affairs Conscription Chiefs of Chaplains : A MC N AF CG Equipment MC : vehicles weapons other AF CG Land Individual weapons Crew - served weapons Vehicles ( active ) Sea All watercraft Ships : A N ( active ) AF CG MSC Weapons : N CG Aircraft : N CG Reactors Air Aircraft World War I active Aircraft designation Missiles Helicopter arms Other Nuclear football Electronics ( designations ) Flags : A MC N AF CG Ensign Jack Guidons Food WMDs : Nuclear Biological Chemical Legend A = Army MC = Marine Corps N = Navy AF = Air Force CG = Coast Guard United States Intelligence Community Intelligence Community Defense Defense Intelligence Agency ( Defense Clandestine Service Defense Attaché System National Intelligence University Missile and Space Intelligence Center National Center for Medical Intelligence Joint Functional Component Command for Intelligence, Surveillance and Reconnaissance ) National Geospatial - Intelligence Agency National Reconnaissance Office National Security Agency ( Central Security Service, Special Collection Service ) Armed Forces Army Intelligence and Security Command Marine Corps Intelligence Office of Naval Intelligence Twenty - Fifth Air Force Coast Guard Intelligence ( Homeland Security ) Civilian Bureau of Intelligence and Research ( State ) Central Intelligence Agency ( Directorate of Operations Special Activities Division Open Source Center Directorate of Science and Technology CIA University ) Drug Enforcement Administration ( Justice ) Federal Bureau of Investigation ( Justice ) Office of Intelligence and Analysis ( Homeland Security ) Office of Terrorism and Financial Intelligence ( Treasury ) Office of Intelligence and Counterintelligence ( Energy ) Director of National Intelligence Director of National Intelligence National Counterterrorism Center National Counterproliferation Center Office of the National Counterintelligence Executive National Intelligence Council Intelligence Advanced Research Projects Activity Joint Intelligence Community Council Chief Information Officer Executive Office of the President National Security Advisor National Security Council President 's Intelligence Advisory Board Homeland Security Council Homeland Security Advisor President 's Daily Brief Other Under Secretary of Defense for Intelligence Army Intelligence Support Activity Joint Worldwide Intelligence Communications System Intellipedia Oversight United States Senate Select Committee on Intelligence United States House Permanent Select Committee on Intelligence United States Foreign Intelligence Surveillance Court Privacy and Civil Liberties Oversight Board Office of Management and Budget Defunct Contingency Fund for Foreign Intercourse Counterintelligence Field Activity Military Information Division Military Intelligence Division Military Intelligence Service Office of Strategic Services Office of Special Plans Strategic Support Branch Federal executive departments of the United States of America Executive Departments Agriculture Commerce Defense Education Energy Health and Human Services Homeland Security Housing and Urban Development Interior Justice Labor State Transportation Treasury Veterans Affairs Former Air Force Army Commerce and Labor Health, Education, and Welfare Navy Post Office War Retrieved from `` https://en.wikipedia.org/w/index.php?title=United_States_Department_of_Defense&oldid=822892770 '' Categories : United States Department of Defense 1947 establishments in the United States Government agencies established in 1947 Military - industrial complex Nuclear weapons infrastructure of the United States United States federal executive departments Hidden categories : CS1 maint : Uses editors parameter Webarchive template wayback links Use American English from August 2016 All Wikipedia articles written in American English Use mdy dates from August 2017 Coordinates not on Wikidata Pages using div col without cols and colwidth parameters Articles with Project Gutenberg links Articles with Internet Archive links Talk Contents About Wikipedia Aragonés Bân - lâm - gú Башҡортса Беларуская Български Català Čeština Dansk Deutsch Eesti Ελληνικά Español Esperanto Euskara فارسی Français 한국어 Hrvatski Bahasa Indonesia Italiano עברית Latviešu Lietuvių Magyar Македонски Bahasa Melayu Nederlands 日本 語 Norsk Polski Português Română Русский Simple English Српски / srpski Srpskohrvatski / српскохрватски Suomi Svenska ไทย Türkçe Українська Tiếng Việt 中文 Edit links This page was last edited on 29 January 2018, at 02 : 58. Text is available under the Creative Commons Attribution - ShareAlike License ; additional terms may apply. By using this site, you agree to the Terms of Use and Privacy Policy. Wikipedia ® is a registered trademark of the Wikimedia Foundation, Inc., a non-profit organization. About Wikipedia

Question: when was the us department of defense established
Answer: September 18, 1947