On June 22, top Bush appointees beat an undignified retreat from the administration’s previous claims — in classified memos that have been leaked recently — of virtually unlimited presidential power to authorize use of torture in wartime interrogations. Six days later, the Supreme Court rejected by 6-3 President Bush’s claim of total power to detain non-Americans at Guantanamo Bay without answering to any court. And eight justices rejected Bush’s denial of due process to Yaser Esam Hamdi, a U.S. citizen whom he has held virtually incommunicado in Navy brigs for more than two years, including 21 months without seeing a lawyer.

The Court’s decisions are a welcome, if ragged, reaffirmation of the rule of law. And it was gratifying to hear the president instructed by his favorite justice, conservative firebrand Antonin Scalia, that "the very core of liberty secured by our Anglo-Saxon system of separated powers has been freedom from indefinite imprisonment at the will of the executive."

What these cases have in common with the saga of the torture memos, I think, is a serious failure of leadership by the president — and, more broadly, by Congress, which has abdicated its responsibilities both to reinforce legitimate presidential power and to check overreaching.

All of this has been bad for national security and good for terrorists:

• By ordering up and later disavowing an indefensibly broad Justice Department claim of executive power to torture, the White House has put itself in the worst of all worlds — international opprobrium for having approved wholesale torture (which it did not do), combined with a newfound CIA wariness of using even mild, legally defensible duress to extract information from captured Qaeda leaders.

• By refusing to provide the military tribunals required by the Geneva Conventions to hear claims of innocence by suspected Qaeda and Taliban fighters held at Guantanamo, Bush may have offended the justices enough to lose a lawsuit that he could have won. The administration had a powerful argument that federal courts lacked the jurisdiction to question its detentions of foreigners outside the United States. Why didn’t the justices buy it? One reason may have been to avoid the appearance of putting their imprimatur on international-law violations that have provoked a worldwide outcry. The result is a morally comforting but legally unpersuasive majority opinion that stretches federal court jurisdiction "to the four corners of the Earth," in the words of the dissenting opinion.

• By making an unprecedented claim of power to lock up, isolate, and interrogate U.S. citizens suspected of being "enemy combatants," potentially for life, without access to lawyers and without any chance ever to appear in court, Bush has convinced eight justices and a broad spectrum of other people that he cannot be trusted to strike a wise balance between liberty and security. This climate of distrust may make it harder for Bush and for future presidents to sell the public on clearly justifiable counter-terrorism measures, such as biometric national identity cards.

• By failing to spell out rules for preventive detention of suspected enemy combatants, Congress has left a dangerous vacuum to be filled by Bush’s grandiose notion of executive power. This has put the courts to the awkward choice of either bowing to Bush’s imperial vision or making up a patchwork of new rules from one case to the next to guide the nation through perilous, uncharted terrain.

The evolution of the Justice Department’s torture memo, as best I can reconstruct it from interviews and news reports, exemplifies how executive overreaching can damage the war on terrorism no less than executive timidity.

In late 2001 and early 2002, the CIA began using coercive methods to get information out of captured Qaeda leaders overseas. But concerns were raised about legal jeopardy and the risk of a public trashing like the one the agency had gotten in the 1970s. So CIA Director George Tenet demanded a legal memo from the Justice Department’s authoritative Office of Legal Counsel promising interrogators and their bosses the broadest possible presidential protection from any future prosecution for torture. The Bush-appointed head of OLC, Jay Bybee, now a federal judge, and some other Justice Department and White House lawyers were reluctant to make that sweeping a claim of presidential power. But they succumbed to pressure from their superiors, and OLC produced the memo that the CIA wanted on August 1, 2002, addressed to White House Counsel Alberto Gonzales. Drafts had been carefully vetted by, among others, the offices of Attorney General John Ashcroft and Gonzales; and Vice President Cheney’s counsel, David Addington, who reportedly pressed for extremely broad claims of presidential power.

There is no evidence that the administration ever approved "torture" (which it has defined extremely narrowly) as a matter of policy. Justice did approve a number of highly coercive, still-classified interrogation methods, such as feigning suffocation and subjecting prisoners to sleep deprivation and "stress positions." Using such methods, the CIA squeezed valuable information out of Qaeda leaders.

Things apparently spun out of control after the Justice Department’s analysis — designed for CIA interrogations of a few high-level terrorists — was adopted by the Pentagon in 2003 and used to justify coercive interrogations of prisoners at Guantanamo and later in Iraq. This was done over strong objections from top uniformed lawyers, based on the military’s long-standing view that rough interrogation methods are ineffective, arguably illegal, and likely to become indiscriminate and excessive.

Those fears were well-founded, as the infamous Abu Ghraib photos showed in late April and May. And the universal condemnation provoked by the photos reached a new crescendo after the leaking in early June of the August 1, 2002, OLC legal memo and a similar March 6, 2003, draft Defense Department memo.

In the hope of quieting the uproar, on June 22 the same White House that had in 2002 virtually ordered OLC lawyers to produce a made-to-order claim of executive power to torture sought to shift the blame to the OLC lawyers for what Gonzales called the memo’s "overbroad" and "unnecessary" passages.

And now, with the big shots ducking and the OLC memo disavowed, "Confusion about the legal limits of interrogation has begun to slow government efforts to obtain information from suspected terrorists, American intelligence officials said … at the start of a critical summer period when counter-terrorism officials fear that Al Qaeda might attack the United States," in the words of a June 28 New York Times report.

Thus has overreaching led to backlash, waffling, legal confusion, and weakness.

In fairness to the officials involved, the moral and legal dilemmas here are so agonizing that it is far easier to criticize than to be confident of the right answers. Had Bush’s people sought to keep their hands clean by giving all captured terrorists the kid-glove treatment demanded by human-rights activists, they could be attacked for being too timid to do what it takes to protect Americans from terrorism.

Still, in my view, this has been a clear failure of leadership by Bush. While signing a deliberately ambiguous, posterior-covering memo in February 2002 calling for "humane treatment" of all detainees, he allowed subordinates to cook up patently outrageous and un-American claims of presidential power to have them tortured.

Instead, Bush could and should have told Tenet that the CIA would have to settle for a legally defensible OLC memo, which would be broad enough to protect interrogators who steer clear of actual torture or unwittingly cross the line in especially exigent circumstances. Had Bush done this, the leaks would have been less damaging; the OLC memo need not have been disavowed; and interrogators would be less confused about what they can do.

Unlike the torture memos, the Supreme Court’s rebuffs to Bush — as distinguished from the presidential overreaching that provoked them — seem unlikely to hurt the war against terrorism. The burden of proof imposed by the Hamdi decision is modest. And the plurality opinion appears to leave room for a limited period of incommunicado interrogation — especially if specified by Congress. Congress could also minimize the burden imposed by the Guantanamo decision by creating special military tribunals there and elsewhere to hear foreign detainees’ claims, with deferential review by a single federal court.

Indeed, these rulings will be very good for our security if they spur Bush and Congress to work together against terrorism. We need a strong presidency to win this war. But we also need an engaged Congress and national unity. As we have seen, when the president bypasses Congress and assumes near-dictatorial powers, the ultimate result is not a stronger presidency, but a weaker one. And that is good for the terrorists.