Dada first appeared in Zurich right after the First World War and spread to Berlin, Paris, Barcelona, and New York. It was really more of a mood than a movement. As the comprehensive show Dada, currently at the National Gallery in Washington, D.C., makes clear, Dada was an enveloping, cathartic reaction to the sickness of modern, mechanized warfare. Its founders hated what they saw as a hypocritical European humanism, whose bromides about honor and justice seemed like fig leaves concealing the self-interested motives that led to the First World War's carnage. Dada had plenty of mottos—one was that the Dadaists wanted to "sow world peace." But its true battle cry might well have been Marx's famous quip in The 18^th Brumaire of Louis Bonaparte to the effect that behind the French republican ideals of liberty, equality, and fraternity lurked the belligerent realities of infantry, cavalry, artillery. The Dadaists saw irrational greed and selfishness behind the claims of "rationality" and "logic." So, they stood Enlightenment values on their heads. Poets like Hugo Ball and artists like Kurt Schwitters wrote and recited nonsense-poetry because they believed that nonsense was a liberation from fake public meanings. Hannah Hoch made a photomontage showing German statesmen bathing nude, implying that behind the pomp and ceremony of official power lay an amoral puniness, symbolized by these bare unlovely bodies. Ball and Tristan Tzara staged utterly anarchic plays whose bawdiness, obscenity, and sheer cacophony outraged respectable audiences, as if to salve the chaos of war with a chaos that didn't hurt. Such antics raise an essential question about Dada. Was it an antidote to the modern madness, or a culturally destructive symptom of it?