Congress can end the war in Ukraine and win a Nobel Peace Prize by enacting a statute withdrawing the United States from NATO — transforming it from a mighty offensive oak into a tiny acorn unalarming to Russia. As early as 1798, Congress nullified a defense treaty with France by statute. A congressional end to United States participation in NATO would be no constitutional novelty. At the very latest, NATO became obsolete in 1991 when its raison d’etre — the Soviet Empire — dissolved. By remaining in NATO and spearheading its expansion to Russia’s borders with 30 members, the United...