The Kurds, a mountain-dwelling Indo-European people, comprise the fourth-largest ethnic group in the Middle East, but they have never obtained statehood. The World War I peace settlement and subsequent Treaty of Sevres (1920) raised hopes of Kurdish independence, but under a subsequent treaty (Treaty of Lausanne, 1923) they were given minority status in their respective countries—Turkey, Iran, Iraq, and Syria—with smaller enclaves elsewhere in the region. Kurds region-wide number between 20 and 25 million, with an estimated 4 to 4.5 million in Iraq, roughly 15% to 20% of the Iraqi population. Most are Sunni Muslims, and their language is akin to Persian; Kurds celebrate the Persian new year (Nowruz) each March 21. Even before the fall of Saddam Hussein, Kurds have had more national rights in Iraq than in any other host country; prior Iraqi governments have allowed Kurdish language use in elementary education (1931), recognized a Kurdish nationality (1958), and implemented limited Kurdish autonomy (1974, with Iraq under Baath Party rule). For the three decades that preceded the U.S.-led expulsion of Iraqi forces from Kuwait in 1991, an intermittent insurgency by Iraqi Kurdish militia (" peshmerga ") faced increasing suppression, particularly by Saddam Hussein's regime. Kurdish dissidence in Iraq was initially led by the Barzani clan, headed by the late storied chieftain Mulla Mustafa Barzani, who founded the Kurdish Democratic Party (KDP) after World War II. He rejected Baghdad's Kurdish autonomy plan in 1974, but his renewed revolt collapsed in 1975 when Iran, then led by the Shah, stopped supporting it under a U.S.-supported "Algiers Accord" with Iraq. Barzani, granted asylum in the United States, died in 1979, and KDP leadership passed to his son, Masoud. Years earlier, a younger, more urban and left-leaning group under Jalal Talabani emerged; it broke with Barzani in 1964 and, in 1975, became the rival Patriotic Union of Kurdistan (PUK). The KDP and the PUK remain dominant among Iraqi Kurds; their differences have centered on leadership, control over revenue, and the degree to which to accommodate Baghdad. The KDP, generally traditional, is strong in the tribal, mountainous northern Kurdish areas, bordering Turkey, whereas the PUK is strong in southern Kurdish areas, bordering Iran. During the first few years of the 1980-1988 Iraq-Iran war, the Iraqi government tried to accommodate the Kurds in order to persuade them not to assist Tehran. In 1984, the PUK agreed to cease fighting Baghdad, but the KDP remained in rebellion. Iraqi forces launched at least two lethal gas attacks against Kurdish targets in 1988, including at the town of Halabja (March 16, 1988, about 5,000 killed). Iraq claimed the chemical attacks were responses to Iranian incursions. During 1987-1989, the height of the Iran-Iraq war and its immediate aftermath, Iraq tried to set up a "cordon sanitaire" along the border with Iran, and it reportedly forced Kurds in many border villages to leave their homes in a so-called "Anfal (Spoils) campaign." Some organizations, including Human Rights Watch, say the campaign killed as many as 100,000 Kurds. During the 1990s, U.S.-led containment of Iraq following the invasion of Kuwait paved the way for substantial Kurdish autonomy. After Iraqi forces suppressed an initial post-war Kurdish uprising, U.S. and allied forces in mid-1991 instituted a "no-fly zone" over the Kurdish areas, protecting the Kurds from Iraqi forces. Later in 1991, Kurdish leaders joined the Iraqi National Congress (INC), a U.S.-backed opposition group, and allowed it to operate from Iraqi Kurdish territory. The Iraqi Kurds set up an administration in their enclave and held elections for a 105-member provisional parliament in 1992. The KDP and the PUK each gained 50 seats; another five went to Christian groups (most of Iraq's 900,000 person Christian community resides in northern Iraq or in Baghdad). Without a clear winner in the concurrent presidential election, the two main factions agreed to joint rule. In October 1992, the Kurdish parliament called for "the creation of a Federated State of Kurdistan in the liberated part of the country" but added that the Kurds remained committed to Iraq's territorial integrity. This caveat did not allay fears among Iraq's Arab leaders that the Kurds would drive for full independence; a concern shared by neighboring states with large Kurdish populations (Turkey, Iran, and Syria). In early 1994, the uneasy KDP-PUK power-sharing collapsed into armed clashes over territorial control and joint revenues. The nadir in PUK-KDP relations occurred in mid-1996, when the KDP enlisted Saddam's regime to help it seize Irbil, the seat of the regional Kurdish government, which the PUK had captured in 1994. The Kurdish regional authority effectively split into KDP and PUK entities. However, the United States spearheaded negotiations that culminated in a September 1998 "Washington Declaration" between the two parties. It was endorsed when the Kurdish parliament reconvened on October 5, 2002, by which time the Kurds and other oppositionists were preparing for a likely U.S. war to overthrow Saddam Hussein. In February 2003, opposition groups met in Kurdish-controlled territory to prepare for post-Saddam Iraq, but these groups were disappointed by a U.S. decision to set up a post-Saddam occupation authority rather than immediately turn over governance to Iraqis. Some Bush Administration officials have attributed the post-Saddam insurgency and instability to this decision. Both before and since the 2003 ousting of Saddam Hussein's regime, the Kurds have been the most pro-U.S. group in Iraq. The Kurds welcomed the U.S. invasion of Iraq and have cooperated with U.S. political and military officials in Iraq since. In return for what they assert has been their consistent pro-U.S. orientation, the Kurds have sought U.S. support for their positions in their various disputes with the other groups in Iraq, and have sought to ensure that the planned December 2011 end to U.S. military involvement does not cause the United States to abandon Iraq, and the Kurds. A wide variety of U.S.-Kurdish issues, including the U.S. drawdown, were discussed when Kurdistan Regional Government (KRG) President Masoud Barzani visited Washington, DC, in late January 2010, and U.S. officials in Iraq meet him regularly. U.S. positions and activities relating to the Kurds are discussed throughout this paper. Although the Kurds welcomed the U.S. decision to overthrow Saddam Hussein militarily, there was virtually no combat in northern Iraq during Operation Iraqi Freedom (OIF), the U.S.-led war that began on March 19, 2003, and toppled Saddam Hussein's regime by April 9, 2003. Turkey did not agree to host U.S. invasion forces prior to the start of the war, and U.S. forces moved up from Kuwait through southern Iraq, and not down from the north. (Turkey reportedly has offered to allow some U.S. troops to depart Iraq through the north, as part of the U.S. drawdown that is to be completed by December 31, 2011.) The Kurds entered post-Saddam national politics on an equal footing with Iraq's Arabs for the first time ever by participating in a U.S.-led occupation administration (Coalition Provisional Authority, CPA). Holding seats on a 25-person advisory "Iraq Governing Council (IGC)," appointed in July 2003, were Barzani, Talabani, and three independent Kurds. In the transition government that assumed sovereignty on June 28, 2004, a top Barzani aide, Hoshyar Zebari, became Foreign Minister (over the objection of many Arab Iraqi figures). This government operated under a March 8, 2004 "Transitional Administrative Law" (TAL)—a provisional constitution that laid out a political transition process and preserved the Kurds' autonomous "Kurdistan Regional Government" (KRG) and its power to alter the application of some national laws. Another TAL provision allowed the Kurds to continue to field their militia, the peshmerga ("those who face death"), now numbering 75,000-100,000. The TAL did not give the Kurds control of Kirkuk (Tamim province), instead setting up a process to allow Kurds expelled from Kirkuk by Saddam to reclaim their homes. Despite opposition from Iraq's Arab leaders, the Kurds succeeded in inserting a provision into the TAL that allowed any three provinces to vote down, by a two-thirds majority, a permanent constitution. The Kurds constitute a majority in Dohuk, Irbil, and Sulaymaniyah provinces, assuring them of veto power. The Kurds supported the constitution in the October 15, 2005, referendum because it appeared to meet their most significant demands. The constitution not only retained substantial Kurdish autonomy but also included the Kurds' insistence on "federalism"—de-facto or formal creation of "regions,"each with its own regional government. The constitution recognizes the three Kurdish provinces of Dohuk, Irbil, and Sulaymaniyah as a legal "region" (Article 113)—the Kurdistan Regional Government (KRG)—with the power to amend the application of national laws not specifically under national government purview; to maintain internal security forces; and to establish embassies abroad (Article 117).