We will not win the terrorism war only by pursuing the money-laundering techniques of the terrorists and their financiers, but that effort will play an important role. Foreign countries must participate in ways they have not done so before, and anti-laundering enforcement is but one tool, with emphasis on infiltration of the terrorists and their allies. We’ll also need to ensure that new money-laundering tools aren’t misused to erode our civil liberties. But recent successes provide reason for hope amidst an attitude of healthy skepticism....