A fundamental principle of international law and morality is that the deliberate murder of civilians is always wrong. In war, it is a war crime. In peace, it is terrorism. No matter the justice of the underlying cause, no end can ever justify that means. This principle unites civilized people in abhorrence of both the crimes of September 11 and the Palestinian bombings of Israeli cafes, restaurants, and buses. It is the core of President Bush’s conviction that we are in a battle of good against evil.

The government’s effort to upgrade airport security over the past six months has been massive and expensive: federalizing airport security forces; confiscating toenail clippers; frisking randomly chosen grandmothers, members of Congress, former CIA directors, and decorated military officers; stationing National Guard troops in airports; putting sky marshals on planes. Has it been effective?

Modern terrorism "renders obsolete [the] strict limitations on questioning of enemy prisoners" required by the 1949 Geneva Conventions, White House Counsel Alberto R. Gonzales wrote in a memo drafted for President Bush (leaked to The Washington Times), "and renders quaint some of its provisions requiring that captured enemy be afforded such things as commissary privileges … athletic uniforms and scientific instruments."

The Bush Justice Department’s focus on preventing terrorist acts rather than solving past crimes is justified by the magnitude of the threat. It’s unfortunate but understandable that by throwing a broad net to catch people who might possibly be terrorists, the government has arrested and detained hundreds of Middle Eastern men on the basis of unconfirmed suspicions that-in the vast majority of cases-have been or seem likely to be dispelled. What’s unfortunate and unforgivable is the mounting evidence that many of these men have been treated badly or abusively while detained, even after being cleared of involvement in terrorism. Such mistreatment will not win the hearts and minds of potential informers, and it will ultimately prove unhelpful to the war on terrorism.

More than 1,180 men, most of them Middle Eastern, have been locked up in connection with the September 11 mass murders with virtually no public disclosure of who they are, where they are, or what crimes or immigration violations they have been suspected of committing. A regulation is quietly slipped into the Federal Register authorizing government officials to listen in on consultations between some of these detainees and their lawyers. A presidential order allows for future military detention and trials of foreigners accused of terrorist war crimes.

Few things concentrate the mind like the prospect of a nuclear mushroom cloud in your own neighborhood. So please concentrate on this: I asked Ambassador Thomas Graham Jr., a sober, respected, retired career arms control official who was President Clinton’s special representative for nonproliferation and disarmament from 1994-97, to quantify the risk of nuclear terrorism. Here is what he said, from Moscow, via cell phone: