The changed methods of warfare in World War II, the maltreatment of prisoners of war that constituted an important part of the war crimes indictments, and the retention of a great number of German prisoners of war by the USSR for several years after the war showed that the 1929 Convention required revision on many points. A new convention, reaffirming and supplementing the 1929 Convention, was signed at Geneva in 1949 and subsequently ratified by almost all nations. It broadened the categories of persons entitled to prisoner-of-war status, clearly redefined the conditions of captivity, and reaffirmed the principle of immediate release and repatriation at the end of hostilities.
Although the North Koreans promised to respect the Geneva Convention in the Korean War, they refused to recognize the impartial status of the Red Cross and denied it access to the territory they controlled. The unprecedented refusal of prisoners to be repatriated, moreover, established a new principle of political asylum for prisoners of war. The governments of North and South Vietnam, parties to the 1949 Geneva Convention, were charged with violating it in the Vietnam War—the North by not permitting full reporting, correspondence, and neutral inspection, and the South by allegedly torturing captives and placing them in inhumane prisons. The national anguish over the Vietnam War was extended for decades after the war's end in part because of the lack of resolution over the POW and MIA (missing in action) issue. While the Pentagon's MIA list still contains names of missing servicemen, the last official prisoner of war was declared dead in 1994.
Combatants captured and held by the United States as a result of its operations in Afghanistan against the Taliban government and Al Qaeda forces were not recognized as as prisoners of war by the Bush administration and were termed "unlawful combatants" instead. This decision was criticized by human rights groups as a failure to abide by international law, and drew criticism from the International Committee of the Red Cross (ICRC) as well. In June, 2004, the U.S. Supreme Court ruled that these prisoners, which the Bush administration had claimed it could hold indefinitely (most of them at the Guantánamo, Cuba, naval base), were not beyond the bounds of U.S. federal law and had the right to challenge their detention.
A month before the ruling, U.S. prestige had suffered a significant blow when it was revealed that U.S. forces had abused Iraqi prisoners in 2003–4. Later revelations suggested that the abuse may have been an outgrowth of U.S. prisoner policy in place since the 2001 terror attacks on the United States, and the ICRC expressed concern that the United States might be continuing to hide prisoners from it, as had been attempted in Iraq. The ICRC subsequently privately charged that U.S. treatment of some prisoners at Guantánamo was "tantamount to torture." Also in 2004 the Bush administration determined that some non-Iraqi prisoners captured in Iraq were not subject to the Geneva Conventions, and that such prisoners could be transferred out of Iraq, as the CIA secretly had done with a small number of prisoners since 2003.