I saw the Ansel Adams: America exhibit at the Bellagio gallery. $15 but worth it. I’ve wanted to see it for the last four years.
And oh yeah, I decided to do a quick Google about the exhibit and I found this: http://rs6.loc.gov/ammem/collections/anseladams/ He took photographs of the Japanese internment.
P.P.S. DC rocks because this is the kind of thing you get to see all the time.