Suppose that the next big terrorist attack on our country comes two weeks after a new Democratic president has taken office. Simultaneous suicide bombings devastate 20 schools and shopping malls around the country, killing 1,500 people. The intelligence agencies believe that at least 20 more trained jihadists, including American citizens, are in the United States planning follow-up attacks.

The president is told that the best hope of stopping a second wave of attacks is to immediately wiretap as many calls and e-mails as possible from and to every private citizen who has been to Pakistan or Afghanistan since 1999. These hundreds of domestic wiretaps, with neither warrants nor probable cause to suspect any individual of terrorist ties, might well violate the Foreign Intelligence Surveillance Act.

The president nonetheless asks the major telephone companies to place the taps for 30 days while the administration seeks congressional approval. He or she also assures the telecoms in writing that the new attorney general has advised that the Constitution empowers the president to temporarily override FISA during such an emergency — a controversial theory never tested in court.

Most Americans would want the telecoms to say yes without hesitation. But the telecoms would have reason to say no — or delay for a few dangerous days to consult their lawyers — if liberals and libertarians get their way in a battle currently raging in Congress.

The issue is whether to immunize these same telecoms retroactively, as President Bush and a bipartisan majority of the Senate Select Committee on Intelligence (including Chairman Jay Rockefeller IV) urge, from liability for having said yes to Bush’s warrantless surveillance program during the unprecedented national crisis precipitated by the 9/11 attacks.

Lakhdar Boumediene was abducted almost six years ago from his home in Bosnia and flown to Guantanamo. He may be a bad guy. Or he may not be. We have no idea. The reason is President Bush’s continuing war on due process, which has blighted the lives of some unknown number of innocent men while doing vast damage to America’s standing in the world.

Boumediene’s petition for release, and those of 62 other Guantanamo detainees, will come before the Supreme Court on December 5. Based on the Court’s previous war-on-terrorism decisions and its unusual alacrity in agreeing on June 29 to hear these detainees’ appeals, Bush seems likely to get his fourth drubbing from the justices since 2004.

Bush deserves to lose. But even the wisest Court decision could barely begin to fix the mess that Bush has made of detention policy. And a judicial over-reaction — along the lines urged by left-leaning human-rights groups — could tie the hands of Bush’s successors. No would-be successor has suggested a sensible alternative policy. And most in Congress punt to the courts (or to Bush) the little-discussed, quintessentially legislative question of what our policy on detaining suspected foreign combatants should be.

So here’s my hope for a three-step quick fix:

1. The justices should signal clearly during the December 5 argument that the due-process-be-damned Bush detention policy is doomed and that Bush’s bloated vision of his own powers will take a big hit if he simply awaits the decision, likely to come in June.

2. These signals will be the cue for Attorney General Michael Mukasey to persuade the president to head off a potentially disruptive defeat by going to Congress to craft a fair, fast, open administrative-detention process for sorting out dangerous detainees from nondangerous ones.

Are we safer than we were six years ago? Emphatically not. The risk that we will see American cities go up in smoke has steadily increased since 9/11. The main reason is not the Iraq war or Al Qaeda’s revival. It’s not the surging numbers of America-haters and would-be terrorists, or the most publicized failings of the Bush administration, or the supposed weakness of the Democrats.

Rather, the central threat is the spread of nuclear weapons and bomb-building programs to more countries. The new nuclear threats already include the unstable Pakistani regime, the evil North Korean regime, and (before long, perhaps) the lunatic Iranian regime. More than anything else, such nuclear proliferation increases the risk that terrorists will get and use nukes.

At least as terrifying is the risk that a false alarm will spur someone to launch a multiple-missile attack — perhaps Pakistan against nuclear-armed India or vice versa, perhaps Russia (by mistake) against America — with catastrophic effects on all involved and, ultimately, on the entire human race.

We must work harder to keep nukes out of the hands of terrorists, especially through underfunded efforts such as the Nunn-Lugar program to secure and dismantle nuclear weapons and materials in the former Soviet Union. We must also better secure our borders to keep terrorists from smuggling in nuclear bombs. But such measures are, at best, fingers in the dike.

If a nuclear bomb went off in an American city today, our leaders would probably not know who did it. But at least the list of suspected sources of supply — North Korea, rogue Pakistani generals, loose nukes in Russia, or terrorists who acquire them — would be short. This would increase the chance of identifying and obliterating the supply source. And that is a pretty good deterrent against any rogue state that might want to attack us through terrorist proxies.

The years of revelations about White House pressure on the Justice Department to concoct far-fetched legal rationales for physically tormenting terrorism suspects, for wiretapping without warrants, and for implementing other Bush policies has obscured a still more fundamental flaw in the Bush policy-making process.

That flaw was the almost exclusive focus on what could be done to captives as a matter of law — as interpreted by aggressive advocates of virtually unlimited presidential war powers — rather than on what should be done as a matter of morality and policy, taking account of careful cost-benefit analysis and past experience.

The result was that while approving in 2002 and 2003 the use of "extreme physical pressure on captives" during interrogations, the CIA and the White House not only disregarded the lessons of history but also engaged in "little substantive policy analysis or interagency consideration."

So said Philip Zelikow, a lawyer who was a senior adviser to Secretary of State Condoleezza Rice from February 2005 until December, in a probing lecture for the Houston Journal of International Law on April 26 (http://www.hjil.org/lecture/2007/ lecture.pdf).

Instead of grappling with the large body of evidence about what has worked best in the past, including the experience of such terror-torn U.S. allies as Israel and the United Kingdom, the administration, Zelikow asserted, pushed interrogators simply to "do everything you can [to break captives], so long as it is not punishable as a crime under American law."

These interrogation policies have been and still are being softened, in a partly secret process. But it is unclear whether President Bush and other top officials have learned that wise policy-making involves more than pushing interrogators to use every harsh method permitted by the Justice Department’s view of the law.