For the bicentenary of David’s death on December 29 1825 — run over by a carriage as he left the theatre, a bourgeois rather than a revolutionary end — the Louvre stages a colossal, riveting retrospective as only this museum can, since it owns most of his paintings, including some too big to move. To this cornucopia are added essential loans, making the exhibition a once-in-a-generation chance to understand this difficult, wily painter, as unwavering in his neoclassical formalism — sculpted bodies, hard contours, polished surfaces — as he was politically opportunistic.