By FRANK RICH

In the immediate aftermath of Sept. 11, the Arab world was riveted by the rumor that Israel was somehow behind the attack on the World Trade Center. Al Jazeera went so far as to report that 4,000 Jews had been given advance notice not to go to work at the towers that day. You'd think that no one in American officialdom would do anything to fan the flames of such noxious fictions, but if so, you'd be underestimating John Ashcroft. As part of his mass dragnet prompted by the attacks on America, our attorney general has rounded up about 50 Israeli Jews, some of whom have been detained for nearly a month on the pretext of minor offenses involving working papers.

Why hold Israelis when there is no evidence linking them to terrorist activity? "We are taking every step we can to prevent future terrorist attacks," said a Justice Department spokesman when queried by Tamar Lewin and Alison Leigh Cowan, the Times reporters who broke the story of the Israeli detainees on Wednesday. "We are leaving no stone unturned." Given that none of Mr. Ashcroft's 1,200 or so arrests to date, whether of Israeli Jews or anyone else, have produced a single charge in connection with the mass murders of Sept. 11, it doesn't seem as if he is even looking in the right quarry. But in his blundering, he has now handed radical Islam a propaganda coup in its war against Israel.

On this bittersweet Thanksgiving weekend, there are many reasons to feel thankful — from the heroism of the Americans who sacrificed their lives for others to George W. Bush's nuanced and so far effective prosecution of the war. Though there have been boisterous nervous Nellies on the right attacking the president's strategy, many of them even angrier at Colin Powell than they are at Bill Maher, there are no gaping fissures in the country's unity. A Los Angeles Times poll last week shows that even Democrats support the president by four to one, no matter how you read the ballots in Florida. And yet on the domestic front, as exemplified by the actions of Mr. Ashcroft, the administration is acting as if America has no inner strength whatsoever. By working its various end runs around our laws, the fearful message is clear: American democracy is too weak to contend with terrorism, and two of the three branches of government, the judicial and the legislative, are not to be trusted.

Even as we track down a heinous enemy who operates out of a cave, we are getting ready to show the world that the American legal system must retreat to a cave to fight back. Our government refuses to identify its many detainees, or explain why they are held, or even give an accurate count. The next stop on the assembly line for these suspects could be a military tribunal, which, as decreed by President Bush in an executive order, is another secret proceeding in which neither the verdicts, evidence nor punishments ever have to be revealed to the public. Thus could those currently in captivity move from interment to execution without anyone ever learning why or where they disappeared. If this sounds like old-fashioned American justice, it is — albeit of such Americas as Cuba and Chile.

If the administration were really proud of how it's grabbing "emergency" powers that skirt the law, it wouldn't do so in the dead of night. It wasn't enough for Congress to enhance Mr. Ashcroft's antiterrorist legal arsenal legitimately by passing the U.S.A.-Patriot Act before anyone could read it; now he rewrites more rules without consulting senators or congressmen of either party at all. He abridged by decree the Freedom of Information Act, an essential check on government malfeasance in peace and war alike, and discreetly slipped his new directive allowing eavesdropping on conversations between some lawyers and clients into the Federal Register. He has also refused repeated requests to explain himself before Congressional committees, finally relenting to a nominal appearance in December. At one House briefing, according to Time magazine, he told congressmen they could call an 800 number if they had any questions about what Justice is up to.

This kind of high-handedness and secrecy has been a hallmark of the administration beginning Jan. 20, not Sept. 11. The Cheney energy task force faced a lawsuit from the General Accounting Office rather than reveal its dealings with Bush-Cheney campaign contributors like those at the now imploding Enron Corporation. The president's commission on Social Security reform also bent the law to meet in secret. But since the war began, the administration has gone to unprecedented lengths to restrict news coverage of not only its own activities but also Osama bin Laden's. A Bush executive order diminishing access to presidential papers could restrict a future David McCullough or Michael Beschloss from reconstructing presidential histories. To consolidate his own power, Mr. Ashcroft even seized authority from Mary Jo White, the battle-proven U.S. attorney who successfully prosecuted both the 1993 World Trade Center terrorists and the bin Laden accomplices in the 1998 African embassy bombings. He has similarly shunted aside state and local law-enforcement officials by keeping them in the dark before issuing his vague warnings of imminent terrorist attacks.

Thanks to a journalist, Sara Rimer of The Times, we now know that one of the attorney general's secret detainees was in fact a local official: Dr. Irshad Shaikh, a Johns Hopkins- educated legal immigrant who serves as the city health commissioner of Chester, Pa. Dr. Shaikh's door was broken down by federal agents who suspected he might be an anthrax terrorist. It's all too easy to see why Mr. Ashcroft wants to hide embarrassing fiascoes like this. But it's also likely that the attorney general wants to hide the arrests he is not making along with the errant ones that he is.

As far as anthrax terrorism goes, evidence like the lethal letter to Senator Patrick Leahy increasingly suggests that the culprit is not a Muslim or Israeli immigrant but, as Mr. Ashcroft's fellow cabinet member Tommy Thompson put it this week, "a disgruntled American" piggybacking on Islamic terrorism. The obvious suspects include those on the Timothy McVeighesque fringes of the Second Amendment cult, who proudly trade in germ war "cookbooks" at gun shows, and those in the anti-abortion terrorist movement, who have a history of wielding anthrax scares as well as explosives in pursuit of their cause.

But is Mr. Ashcroft pulling in, say, any of America's own Talibans, like the Army of God, with his dragnet? It seems unlikely, given that these organizations, which are big on advertising their own self-martyrdom, haven't reported any such detentions. A cynic might think that domestic extremists who share the attorney general's antipathy to abortion and gun control — and are opposed to the likes of Mr. Leahy and Tom Daschle — receive a free pass denied to suspicious-looking immigrants. Yet that cynicism could be dispelled in a second if Mr. Ashcroft trusted the public, and for that matter his former colleagues in Congress, to carry out his brand of law enforcement in daylight.

While Mr. Ashcroft may abhor such openness because he's pursuing a political agenda of his own, it's also possible that less malevolently, he's just trying to hide his failure at getting the job done. There's nothing in the man's history as either a governor or senator to suggest that he's the Rudy Giuliani his assignment calls for, and despite his strong-arm policing since Sept. 11, he has no visible results. His latest scheme — to spend 30 days interviewing 5,000 more immigrants who, he says, fit "a set of generic parameters" — inspires so little confidence that some local police chiefs are in open revolt against it.

Mr. Ashcroft likens himself to Robert Kennedy, who also at times warped constitutional protections in ravenous pursuit of criminality. But among the many differences between the men is the fact that Kennedy actually busted criminals. If another 30 days and 5,000 interviews pass with no breakthroughs, who knows what grandiose new plot Mr. Ashcroft will devise, and at what civic price, to make himself look like Dick Tracy. At a time when most Americans feel confident that the war on terrorism is going as well, if not better, than could be expected, his every ineffectual and extralegal move waves an anomalous but still chilling white flag of defeat.