A bipartisan congressional consensus seems to be emerging: First, the Bush administration’s eavesdropping program (or something like it) should be continued to try to avert Al Qaeda attacks. Second, such spying should be subjected to oversight by Congress and the courts, regardless of whether President Bush wants it to be.

What kind of oversight? And how should Congress update the Foreign Intelligence Surveillance Act of 1978 to deal with the unprecedented magnitude of the internal security threat posed by jihadists who covet doomsday weapons? If we get the answers wrong, we will end up with weaker defenses against terrorism, insufficient protections against the abuse of civil liberties, or both.

The most specific proposal so far is terrible — Senate Judiciary Committee Chairman Arlen Specter’s notion that Congress should ask the secret Foreign Intelligence Surveillance Court to weigh in on whether the program is constitutional. That would amount to a request for an advisory opinion on a broad matter of policy. Courts have spurned such requests since the dawn of the Republic. The reason is that their constitutional mandate is to resolve individual cases and controversies — not to help set broad policies, let alone to micromanage presidential spying on the enemy in wartime.

Specter aside, we need to adapt the judicial role in enforcing the Fourth Amendment ban on "unreasonable searches and seizures" to current realities. The courts have traditionally decided in advance (or, when speed is crucial, after the fact) whether the government has "probable cause" to target an individual for searching or electronic eavesdropping. But as Judge Richard Posner of the U.S. Court of Appeals for the 7th Circuit noted this Wednesday in a Wall Street Journal op-ed, this model is "hopeless as a framework for detecting terrorists," which amounts to "a search for the needle in a haystack."

I argue below that President Bush and his aides are twisting facts as well as law in their obsession with avoiding independent oversight of his warrantless electronic surveillance program. But I begin with three concessions.

First, the Foreign Intelligence Surveillance Act of 1978 is outdated. It bars and impedes some forms of electronic spying that may well be essential in an era of suicidal terrorists who seek doomsday weapons and are bent on mass murder.

Second, the president’s inherent constitutional power to protect the nation justified his authorization in the weeks after 9/11 (but not indefinitely) of a National Security Agency surveillance program that would otherwise have been a criminal violation of FISA.

Third, the administration may well be right in saying that leaks and media disclosures of classified information have done serious damage to national security in a few cases and possibly some damage in the case of Bush’s NSA program.

But is Bush credible when he claims that the leaking to and the disclosure by The New York Times on December 16 of aspects of the previously secret NSA program "puts our citizens at risk"? And was Attorney General Alberto Gonzales credible when he testified on February 6 that to submit to congressional regulation and judicial oversight would mean "effectively killing the program" by blowing secrets essential to its effectiveness — and that this view was the "consensus" of congressional leaders whom the administration had briefed?

I don’t believe them, except perhaps as to the inertness of some congressional leaders. And the Bush and Gonzales track records inspire no trust in their veracity. Especially when Bush suggests that the NSA program eavesdrops only on international communications involving "known Al Qaeda and/or affiliates" (emphasis added).

Libertarians and Democrats say that President Bush’s warrantless surveillance program is a clear violation of the Foreign Intelligence Surveillance Act. Bush and some impressive intelligence professionals say that the program is a vital early-warning defense against Qaeda terrorists and thus an exercise of the president’s inherent constitutional power to defend the nation; this power, they say, trumps any conflicting provisions of FISA.

Both sides are right. But both are wrong to spend their time bickering over the legality or illegality of what Bush has authorized the National Security Agency to do. They should be focusing on how to amend FISA to provide independent checks on abuse of the NSA program without compromising its effectiveness in preventing mass murder.

"FISA is outdated and inadequate and urgently needs reform to make it effective against the jihadist threat," says Philip Bobbitt, a Texas law professor and defense expert who held a high position in President Clinton’s National Security Council and is writing a book on the war against terror.

"The critics are insisting on rules that fly in the face of the strategic realities," Bobbitt adds. "But when the president secretly decides a measure is unconstitutional, and neglects to say so (much less why), he sacrifices the legitimacy that comes from public understanding of his decision and undermines our system of public consent."

Bobbitt is exactly right, on all counts. As to Bush, the man never consults Congress when he can make a grandiose claim of executive power instead. He sometimes seems to have forgotten that the goal is "fighting terrorism, not avoiding oversight," as my colleague Jonathan Rauch detailed in the January 7 issue of National Journal.