War does not habitually inspire major new art movements. World War One? It spawned two: dada and surrealism.
If dada makes you think of urinals and photomontage (as it should), surrealism will to take you into dreams, desires, and outright hallucinations. In the realm of pure paintings, it is surrealism that has most easily entered the popular mainstream, as with Salvador Dali's melting clock and René Magritte's pipe that is not a pipe.