President Bush signed the Patriot Act last week. The new anti-terrorism law has its critics. Some object to the law's intrusions on civil liberties. They cite the provisions for extended detention, new powers to spy on Americans, a lack of controls on use of information, a greater ability to freeze and seize assets and an overly broad definition of domestic terrorism.

Others express concern about the process. The Patriot Act represents the most radical change in police powers in decades, and codifies counterterrorist measures previously rejected by Congress as too intrusive.

Still, there were few hearings and little debate. Many representatives didn't have an opportunity to read the House version before the vote.

In the Senate, the bill bypassed Judiciary Committee markup and went straight behind closed doors. Presented with a thumbs-up or thumbs-down option,

and with little opportunity to amend the bill, few lawmakers were willing to risk being seen as "soft on terrorism."

There is another issue, however, and it has received little attention. It is the issue of effectiveness. Will these new police powers help to stop terrorism? The obvious and intuitive answer would seem to be yes.

If the police have more power to collect information, they should be able to catch more terrorists. That sounds logical, but once you scratch the surface of that argument the problems become obvious.

The Patriot Act's key provisions focus primarily on data collection. The underlying assumption is that the real problem here is a lack of information. The history of intelligence failures suggests, however, that often the problem is not a lack of data, but rather making sense of the data you already have. Sometimes it's the case of the left hand not knowing what the right hand has. After the 1993 bombing of the World Trade Center, the FBI discovered that it already had copies of maps and detailed plans of the attack before it happened.

Other times, it reflects the difficulty of weighing conflicting pieces of information or of applying existing information to new contexts. These tasks require human interpretation and judgment. September 11 was not the first suicide attack against the United States. The 1983 bombing of the Marine barracks in Beirut, Lebanon, the 1998 embassy bombings in Nairobi, Kenya, and Dar-es-Salaam, Tanzania, and the attack on the destroyer Cole in Yemen all involved suicide bombers. Imagining that suicide bombers might strike the United States did not require new information. It required a more imaginative use of the information already in hand.

So what about the September 11 attacks? Was it a lack of information,faulty data analysis, organizational dysfunction, or some combination of all three? The simple answer is that we don't know. No official investigations have been completed. Congress, not wanting to look like it was pointing fingers at a time of national crisis, decided to hold off on any inquiries. In time, we will know what happened. Once the witnesses are deposed and the records subpoenaed, the American public should have a clearer idea of what went wrong in the weeks and months leading up to September 11.

The irony, of course, is that we will find out what needs fixing after having already passed an anti-terrorism law. In theory, the government could go back and repeal the legislation and replace it with something else. History suggests, however, that passing anti-terrorism laws is much easier than repealing them. What lawmaker will vote for a repeal, and risk that a repeal is followed by a terrorist act? Will police or intelligence bureaucracies want to give up expanded powers? The record is clear. In country after country, temporary measures intended to combat terrorism have became near permanent powers of the state.

Compelled by events, the president and Congress have moved swiftly to redress the failures of September 11 -- perhaps too swiftly. We now have a law that is intended to solve problems we have yet to identify. The Patriot Act may improve our ability to fight terrorism. On the other hand, it may have no effect whatsoever. It could even make things worse. Like the patient who chooses a medicine before knowing his illness, the government has passed a law without knowing what needs a remedy. It is a major gamble, and for the country -- as for the patient -- the effects may be severe and long lasting.

The U.S. government is expert at presenting well-honed Pentagon briefings describing American military action. Decisions are made regularly about how much detail the military believes can be presented without endangering U.S. troops. But only late last week -- after two weeks of anthrax scares in the United States -- did we begin to see similarly professional efforts to inform U.S citizens about the domestic threat they faced.

The Bush administration has right stated that we are and must be prepared to use the full arsenal of our defense capabilities to respond to the heinous acts of terrorism directed against the United States and the world on 11 September 2001. President Bush clearly stated that the use of military force will be a part of our campaign to fight terrorism and defend our homeland. Administration officials also cautioned Americans not to expect a massive military response but rather a longer, and at times invisible, diplomatic and financial campaign aimed at crippling terrorists. This is an astute, but incomplete, use of U.S. force.

The September 11, 2001, attacks on the World Trade Center and the Pentagon have shown that well-organized global terriorist groups bent on causing mass murder and destruction are no longer hypothetical. There can now be little doubt that if such terrorists could acquire weapons-usable nuclear materials across a city, they would likely attempt that as well. Under these circumstances, measures to further strengthen the protection of nuclear materials and muclear installations are urgently needed.

This report first reviews the need to strengthen protection of nuclear materials and muclear reactors against terrorists and thieves and then examines the need for better trianing of those charged with protection responsibilities to meet this challenge. Our research suggests that security practices vary significantly country to country, giving thieves and terrorists opportunities to steal nuclear material or to sabotage nuclear facilities in some countries that they do not have in others.