Place it at the end of a setup showing a trivial defeat, then follow it with a deadpan reaction for contrast. A short reaction clip after the declaration keeps the joke moving, while putting another sound before it risks crowding the punch.
About this sound
This is a short French voice clip saying 'On a fait la guerre!' in a bold, declarative tone, lasting about 1.4 seconds. It lands as mock-heroic and overblown, turning a small disagreement or everyday struggle into a grand battle. The humour comes from that gap between the serious delivery and the trivial situation it is used for, making it feel triumphant, theatrical and deliberately dramatic.