Contrary to the fearful voice of Associate Justice Robert Jackson dissenting in Korematsu vs. United States (1944), emergency powers asserted by presidents in times of war have not turned into loaded guns lying around for misuse by any zealous official who claims an urgent need. History speaks otherwise. During the Civil War, for instance, President Abraham Lincoln extraconstitutionally summoned an army, expended unappropriated funds, unilaterally suspended the writ of habeas corpus, and suppressed speech friendly to the Confederacy. Congress belatedly ratified Lincoln's legislative usurpations. They were not repeated during the war. Neither did they establish presidential war principles that crept...