Washington ? In a major reversal of a keystone policy in its war on terrorism, the Bush administration announced Tuesday that all detainees in U.S. military custody, including those at Guantanamo Bay, Cuba, are entitled to Geneva Conventions protections that prohibit humiliating treatment and torture.

The change reflects the Pentagon’s response to the Supreme Court’s 5-3 decision last month that struck down the administration’s makeshift formula for military tribunals at Guantanamo, declaring their procedures unconstitutional and a violation of Geneva Conventions obligations.

The two-page Pentagon memo repudiates a core element of the legal foundation of President Bush’s approach to dealing with terrorism. Bush and his legal advisers initially had said the Geneva Conventions didn’t apply to the war on terrorism because it was a new type of conflict that demanded more aggressive action.

In a 2002 memo, then-White House counsel Alberto Gonzales told Bush that this nontraditional war “renders obsolete Geneva’s strict limitations on questioning of enemy prisoners and renders quaint some of its provisions.”

Vice President Dick Cheney and White House spokesmen made clear in many public statements since 2002 that they didn’t think that terrorism suspects deserved the rights that the Geneva Conventions granted to enemy soldiers. At the same time, Bush has said repeatedly that his administration is committed to complying with the Geneva Conventions, but he’s also reserved the right to waive them if he sees fit as commander in chief.

The new Pentagon memo doesn’t change captives’ status as enemy combatants – not prisoners of war – nor does it suggest that practices will change at Guantanamo, the remote interrogation and detention outpost at a U.S. naval base in southeast Cuba where commanders defend the treatment of its 450 captives as humane.

The new memo, signed by Deputy Defense Secretary Gordon England, declared that Article 3 of the Geneva Conventions “applies as a matter of law to the conflict with al-Qaida.” His memo doesn’t, however, embrace all the terms of the Geneva Conventions.

Article 3 of the international standards prohibits “outrages upon personal dignity, in particular humiliating and degrading treatment.”

The administration’s policy shift repudiates a six-week burst of early Guantanamo practices, which FBI agents described in internal e-mails as involving chaining captives for so long that they urinated and defecated on themselves. Military guards or interrogators also allegedly tethered captives to dog leashes, wrapped them in Israeli flags and exposed them to extremes of hot, cold and blasting music to break their resistance and spill secrets.

The Pentagon estimated Tuesday that it had about 14,000 captives in U.S. military custody: 13,000 in Iraq, 550 in Afghanistan and 450 at Guantanamo.

The Pentagon announced the policy change Tuesday as Senate Judiciary Committee Chairman Arlen Specter, R-Pa., convened the first of three congressional hearings this week on how to try war-on-terrorism captives as alleged war criminals without relying on hearsay evidence and possible secret, coercive interrogations.

In its 5-3 decision last month in Hamdan v. Rumsfeld, the Supreme Court invited Congress to write a law governing military trials of detainees in the war on terrorism. At issue is how to shape a court that protects classified information, allows the government to offer a robust prosecution and permits alleged war criminals to confront their accusers within a framework of law.