The Liberty Memorial WWI museum's also excellent. Better in some ways than what they've got at Les Invalides in Paris. One of a handful of things in the city worth adjusting an itinerary or travel route to see/experience.

Incidentally, the Middle Eastern restaurant (Habashi House, I think it's called) on the City Market square where the Steamboat Arabia museum's located is pretty damn good. Coffee shop in the corner's got good sandwiches. Avoid the Indian place—not good.