Senator Specter has pressed the question: why not submit the ongoing NSA program to the FISA court now to seek its approval. It sounds very reasonable, but its core assumptions miss the point in two key ways.

First, separation of powers. It is the President, not the Judiciary, which is supreme in matters of foreign intelligence collection and national security. It is, moreover, wartime. It is the President in our system who makes the ultimate judgment about what must be done to protect the public from foreign threats – even in peacetime. It would not be proper constitutionally for the President to delegate that prerogative to another branch. Thus, if the FISA Court reviews the NSA program and opine against it, what is the President supposed to do? Discontinue a program that provides an early warning system against what could be a devastating attack? That is a call we elected him to make – the FISA court has no place making such judgments.

Second, what the NSA program is designed to accomplish is different from what FISA is designed to accomplish. The NSA program is an early warning system to prevent against sudden attack from a foreign power conducting an attack. FISA is designed to set up a procedure for collecting intelligence against the domestic operatives of foreign powers. The fact that the program might not pass muster under FISA in the view of the FISA court judges would in no way mean the program is improper or justify its termination.

A good comparison might be public safety searches. The state sets up check points to search randomly as people try to get on airplanes (to ensure they are not armed), or as they try to get on highways (to ensure they are not impaired). They do this without warrants. They could not proceed the same way if their purpose was to collect evidence for use in court – for that they’d need a warrant based on probable cause. But the purpose of the public safety search is not the same as the criminal search.