Created on December 15, 1791, the Second Amendment to the United States Constitution is the part of the United States Bill of Rights that establishes the right of citizens to possess firearms for lawful purposes. It says, "A well regulated militia, being necessary to the security of a free state, the right of the people to keep and bear arms, shall not be infringed."

Background 
When America was being colonized by European countries, firearms were very important to colonists. When Europeans came to America, they brought with them the idea of land ownership by an individual. They received this right from their king through land grants. This was completely foreign to Native Americans who considered a particular territory belonged to the tribe. Colonists defended their claims against Native Americans and other Europeans whose kings may have granted them the same lands. They also needed firearms for hunting. In many towns and villages, men were required to own firearms for the defense of the community. Most colonists coming to America in the 17th century had no experience as soldiers. The British kept few soldiers in the colonies, and colonists soon found they needed to establish militias. 

Colonies had militia laws that required every able-bodied white man to be available for militia duty and to provide his own arms. In 1774 and 1775, the British government, which now had a larger presence, attempted to disarm American colonists. This caused the colonists to form private militias, independent of any control by the governors appointed by the British government. The Minutemen who fought the British Army at the Battles of Lexington and Concord were an independent militia.  

After the American Revolutionary War, the framers of the Constitution, like most Americans of the time, distrusted standing (permanent) armies and trusted militias. After the Revolutionary War, Americans trusted state militias to defend the country. The Articles of Confederation, the new nation's first constitution, called for each state to maintain a well-armed militia. Congress could call up the militias to defend the country against any foreign power.  However, Congress could only form a standing army if nine of the thirteen states approved. This was one of the weaknesses that led to the Constitutional Convention of 1787 and a new constitution.  

In the 18th century, the word "army" meant mercenaries. Americans distrusted standing armies and were afraid they could be used to take over the country. People still remembered Oliver Cromwell and his military dictatorship in England.

State constitutions 
Virginia was one of the first colonies to adopt a state constitution. They included the words: "a well regulated Militia, composed of the body of the people, trained to arms, is the proper, natural, and safe defence of a free State." Other states followed with similar wording in their own constitutions. Pennsylvania declared: "the people have a right to bear arms for the defence of themselves and the state; and as standing armies in the time of peace are dangerous to liberty, they ought not to be kept up; And that the military should be kept under strict subordination to, and governed by, the civil power." 

In 1781 the Continental Congress approved the Articles of Confederation. This recognized that the thirteen original states had the power to govern themselves. They acted collectively to have a congress, but did not provide any money to run it. There was no president and no court system. This confederation of states proved to be a very poor form of central government.

Philadelphia Convention of 1787 
The Constitutional Convention met in Philadelphia, Pennsylvania from May 25 to September 17, 1787. The purpose of the Convention was to revise the Articles of Confederation. But it became clear that many of its members, including James Madison and Alexander Hamilton, wanted to create a new government rather than fix the existing one. The delegates elected George Washington to preside over the Convention. They eventually agreed on agreed on Madison's Virginia Plan and began to make changes. The result was the Constitution of the United States and the present form of government.

Bill of Rights 
The constitution debate at Philadelphia caused two groups to form: the Federalists and the Anti-federalists. The federalists wanted a strong central government. The anti-federalists wanted the state governments to have more power. The vote on the new Constitution was passed on a promise by federalists to support a Bill of Rights to be added to the Constitution. 

Originally, Congress suggested 12 amendments to the states. However, the states only ratified ten. The Bill of Rights, as the first 10 amendments came to be called, originally applied to the national government rather than to states. Many states already had their own Bill of Rights. The Bill of Rights was ratified and went into effect in 1791.

Different interpretations 
The Second Amendment was a result of several proposals being combined and simplified into just 27 words.  This simplification has caused many debates over gun ownership and individual rights. Historians, judges and others have repeatedly looked for the intended meaning by the 18th century writers of this amendment.  Different interpretations of the Second Amendment still cause public debates about firearm regulations and gun control.

Capitalization and punctuation 
In 2007, the United States Court of Appeals for the District of Columbia Circuit heard a case called Heller v. District of Columbia.  At the time, it was illegal for regular Americans to have a gun in Washington, D.C. To decide whether this was against the Second Amendment, the court looked very closely at capitalization and punctuation in the Amendment to try to figure out exactly what the framers meant.

Judge Laurence H. Silberman wrote the Court's decision. It made the ban on guns by the District of Columbia invalid. The decision was based on the second comma (after the word "state") as proof that the Second Amendment allows individuals the right to carry a gun. This is in addition to state's rights to maintain militias.

The Second Amendment ratified by the States and approved by the Secretary of State, Thomas Jefferson, said:
"A well regulated militia being necessary to the security of a free state, the right of the people to keep and bear arms shall not be infringed".

The version passed by Congress and signed by President George Washington (but never ratified by the States) said:
"A well regulated Militia, being necessary to the security of a free State, the right of the people to keep and bear Arms, shall not be infringed."
On June 25, 2008, the Supreme Court agreed with the Court of Appeals' decision.  (In the Supreme Court, the case was called District of Columbia v. Heller.)

Landmark decisions 
 In 1939, the U.S. Supreme Court made a landmark decision in United States v. Miller (307 U.S. 174 (1939)). The Court determined that Congress could keep people from having certain weapons (in this case, a sawed-off shotgun) because the shotgun would not help maintain a well regulated militia. The Court said the Second Amendment's purpose was to ensure the effectiveness of the military.
 The case District of Columbia v. Heller (554 U.S. 570 (2008)), was another landmark case. It was the first time in almost 70 years that the Supreme Court applied the Second Amendment to a review of gun control laws. The Supreme Court of the United States held in a 5-4 decision that the Second Amendment to the United States Constitution applied to the Federal district and protects an individual's right to possess a firearm for lawful purposes. This struck down the D.C. handgun ban because it violated citizens' Second Amendment rights. The decision also called United States v. Miller an exception to the general rule that Americans may possess firearms. The Court said:
 People who obey the law cannot possibly use sawed-off shotguns for any legal purpose
 Laws about similar weapons that cannot be used for any legal purposes would not violate the Second Amendment
 Laws that would keep criminals and the mentally ill from having guns would not violate the Second Amendment.
 In McDonald v. Chicago (561 U.S. 742 (2010)), the Supreme Court said in a 5-4 decision that the city of Chicago could not make it illegal for citizens to own handguns. The Court ruled that the right of an individual to "keep and bear arms" protected by the Second Amendment is incorporated by the Due Process Clause of the Fourteenth Amendment. The court held that it applies to the states.

Notes

References

Other websites 

 High Court’s Gun Ruling Cites Intent of 14th Amendment
 Benjamin Netanyahu just made the single best argument EVER for the Second Amendment 
 Should guns be banned in America?

United States Bill of Rights
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