Massive compromises of our nation's most sensitive military secrets during the past 20 years have forced an urgent review of our laws to deter, detect and prosecute those who commit espionage against the United States. Convicted traitors like the Walker family of spies, Jerry Whitworth, Ronald Pelton and William Kampiles have inflicted grave damage by transferring vital defense information to foreign powers.

There is no official estimate of the cost of remedial measures necessary to counteract the espionage, but it is conservatively believed to range in the billions. Beyond the dollars, the spying has endangered our national security to such a breathtaking extent that we can all be thankful that war did not break out while some of our most sensitive secrets were compromised.

An intensive study of the recent spy cases reveals dramatic changes in the nature and character of espionage. Recognition of these changes can provide a promising basis for shoring up federal espionage laws to help protect our secrets without endangering our civil liberties. In the recent past, our counterespionage efforts have been premised on the outmoded assumption that the traitors are ideologues sympathetic to our nation's adversaries or that they are individuals capable of being blackmailed or coerced into revealing our secrets. Modern-day espionage simply does not fit neatly into these patterns, with the result that our efforts at prevention and detection have fallen far short of the mark.

Alarmed by the dramatic compromises of military secrets, the chairman and vice chairman of the U.S. Senate Intelligence Committee--Sens. David L. Boren (D-Okla.) and William S. Cohen (R-Me.)--recently convened a bipartisan advisory panel of experienced citizens to analyze the changing face of espionage and make recommendations. The panel, chaired by industrialist Eli S. Jacobs, systematically reviewed the 19 leading espionage cases brought since 1971 and studied about an equal number of cases in which prosecution for espionage was not feasible for various, sometimes highly classified, reasons.

The panel made several important findings: The motivating factor in most of the 19 cases was money--not ideology or blackmail but a naked desire for money. The winding down of the Cold War is likely only to accelerate this shift in motivation.