The United States enjoys a strong legacy of defense cooperation with Turkey, both bilaterally and in the North Atlantic Treaty Organization (NATO), dating from the onset of the Cold War. For both countries, mutual cooperation has major implications for national security priorities in Turkey's surrounding region—particularly the greater Middle East. A more independent Turkish foreign policy course—reflected in recent international events involving Iran, Israel, and other countries—has raised concerns among some Members of Congress. This, coupled with a decline of the military's influence in Turkish society, may affect prospects and present challenges for bilateral and NATO defense cooperation, while also generating ongoing debate over which country needs the other more to pursue and achieve its national security objectives. A challenge for U.S. officials—particularly in the White House, the Defense Department (DOD; both civilian and military branches), and the State Department—is to adjust future modes of bilateral interaction with Turkey on defense matters to account for greater fluidity within the internal Turkish civil-military power structure. Determining proper interlocutors for both countries on different but interrelated questions of (1) grand strategy (which involves political objectives beyond pure military matters), (2) military strategy, and (3) tactical and operational objectives could lead to an approach that is more multidimensional than the well-established pattern some observers see in which the State Department and other U.S. officials rely on the "Pentagon to wield its influence." Areas of potential interest or concern for Congress, as well as other U.S. policymakers, include the following: Overall Defense Relationship : Reconciling regional perceptions of growing Turkish influence and declining U.S. influence with persisting Turkish interest in defense cooperation to address immediate security and deterrence needs. NATO/Missile Defense : Turkey's role in NATO, both in (1) defining the scope of alliance action and objectives in possible cases of intervention, such as Libya; and (2) regarding aspects of alliance-wide defense, such as an approved missile defense system that could feature a radar station and other elements in Turkey to counter threats from Iran and elsewhere. Iraq and Afghanistan : Cooperating with Turkey to achieve stability and a reduced threat of terrorism from Iraq and Afghanistan through (1) joint counterterrorism efforts, (2) use of Turkish bases and territory for cargo transport, (3) possible arms sales, and (4) direct involvement of Turkish non-combat troops (in Afghanistan) and trainers. Israel : Addressing implications of increasingly distant Turkey-Israel relations on U.S.-Turkey defense cooperation. Armenian Genocide Resolution : Continuing defense cooperation with Turkey in light of a possible adverse Turkish reaction to a potential U.S. congressional resolution or presidential statement characterizing World War I-era actions of the Ottoman Empire against Armenians as genocide. Expectations regarding the likely nature and extent of a possible adverse Turkish reaction vary. Future Prospects for Various Modes of Defense Cooperation : These include (1) joint exercises and missions; (2) stationing of U.S./NATO personnel and arms (including a reported nuclear weapons arsenal) in Turkey; (3) forms of defense-related U.S. aid, including International Military Education and Training; and (4) defense industrial cooperation. Turkey's NATO accession in 1952 during the early years of the Cold War was premised upon the concept of a "mutuality of benefits." Turkey received U.S. security guarantees against Soviet aggression. In return, the United States and its other Western allies could (1) station and base troops and equipment in Turkey for defensive and intelligence-gathering purposes, (2) count on Turkish control over Soviet access to the Mediterranean through the Bosporus and Dardanelles straits and on Turkish co-belligerency in case of an attack, and (3) contain Turkish-Greek tensions within the NATO umbrella. Although events over the last few years have strained U.S.-Turkey defense cooperation to some extent, tension in the bilateral relationship is not new. According to one scholar, "Apart from a honeymoon in the early 1950s, the US-Turkish alliance has always been troubled." Turkey's relations with Greece and its involvement in Cyprus have been the focus of many of these troubles. When in 1974 Turkey sent troops using U.S.-supplied arms to intervene on behalf of the Turkish Cypriot minority, Congress responded by placing an embargo on U.S. military grants and arms sales to Turkey that lasted from 1975 until 1978, despite objections voiced by the executive branch. The embargo delivered a serious blow to the Turkish military's operational readiness. Turkey, in turn, closed U.S. defense and intelligence installations on Turkish territory throughout the period of the embargo (except for those installations that had a purely NATO function). In addition, according to a 2005 article in the journal Turkish Studies , "The resentment and loss of confidence in the US transformed the alliance to a great extent and made Turkey focus on two important strategic priorities from then onwards: to diversify the sources of arms imports and to improve the development of a domestic arms industry." Yet, some believe that the nature and degree of U.S.-Turkey tensions, and how they affect mutual threat perceptions and defense priorities, might be changing. Longtime Turkey analyst Henri Barkey of the Carnegie Endowment of International Peace wrote in 2010 that "Turkish-American relations were always difficult and acrimonious even in the best of times…. What is different now is that the issues over which Turkey and America differ are far more numerous and complicated than in the past." The vote of the Turkish Grand National Assembly (Parliament) in 2003 not to allow U.S. troops to use Turkey's border with Iraq as a second front in their invasion of the country showed the United States that in its defense relationship with Turkey, it could no longer rely solely on past legacies of cooperation and its close ties with the Turkish military. The onset of more numerous and complicated differences within the U.S.-Turkey alliance may be reflected in Turkish popular sentiment toward the United States. Results from a December 2010 poll stated that despite the longtime alliance, and despite several potential threats along Turkey's borders, the Turkish people see the United States as its biggest external threat by a wide margin. This apparent sentiment exists within a context of Turks' generally low favorability ratings for foreign countries, partly based on historical concerns about encirclement by outside powers—particularly the West and Russia. Reports posit that the 2003 U.S.-led invasion of Iraq is a major shaper of the Turkish people's threat perception, along with U.S. closeness to Israel and congressional action on Armenia. However, a British Broadcasting Corporation (BBC) poll released in March 2011 indicates that—though still negative on balance—Turkish perceptions of U.S. influence in the world have improved significantly from a year earlier. Future trends in these perceptions are likely to influence democratically elected Turkish leaders' approaches to strategic cooperation. Since 1948, the United States has provided Turkey with approximately $13.8 billion in overall military assistance—$8.2 billion in monetary and in-kind grants and $5.6 billion in loans. However, the end of the Cold War and Turkey's increasing economic and military self-sufficiency led to the discontinuance of most aid. Current annual military and security assistance is limited to International Military Education and Training (IMET); International Narcotics Control and Law Enforcement (INCLE); and Nonproliferation, Antiterrorism, Demining and Related Programs (NADR) funds. For a more detailed breakdown of this assistance, see Table 1 below; and for a historical overview and chronology of U.S.-Turkey defense cooperation, see Appendix A . Arguably, Turkey is a more significant ally for the United States at present than during the Cold War. With several challenges to U.S. national security emanating from the greater Middle East, the United States has already shown that it seeks to use Turkey's geographic location for its advantage, and it is likely that future U.S. regional interests will dictate a similar U.S. outlook. Given Turkey's location near several global hotspots, the availability of its territory for the stationing and transport of arms, cargo, and personnel remains valuable for the United States and NATO (see Figure 1 and " Bases and Transport Corridors " below). In addition, Turkey, with its sizeable armed forces and modern weapons systems, is considered to be among the strongest military powers in its region, and continuing Turkish economic growth and increases in domestic military spending and arms exports support the view that it will play a major role in regional security for years to come. As Turkey's regional influence expands through economic, political, and cultural means, its importance has arguably increased for the United States on issues of global significance that include Iraq, Iran, Afghanistan, and Israeli-Palestinian issues. In early 2011, Turkey's regional role has arguably become even more prominent—exemplified by its significant involvement politically and militarily on the question of NATO's intervention in Libya—as political change and unrest generates international debate about links between internal governance, humanitarian and civil society issues, and regional security. Moreover, Turkey's growing importance as a regional energy transport hub whose supply sources are not limited to (even though they include) Russia and Iran elevates the continued importance of Turkey's security for world energy markets. This affects both U.S. and Turkish calculations of the mutual benefits and leverage of defense cooperation. The United States hopes that involving Turkey's military and territory in various defense initiatives (such as in Libya and Afghanistan, and with NATO missile defense) both provides greater influence for the United States with regional actors and politically legitimizes U.S. actions to Muslim populations. Turkish leaders use the importance the United States confers upon Turkey's role both to seek benefits from the United States and to elevate their prestige in dealings with other countries.