No due to government shut down all are closed but there are exceptions that certain institutions are open and it would be posted in their website.it is open 364 days according to the owner
The Smithsonian American Art Museum is open daily, 11:30 A.M.–7:00 P.M. We're open 364 days a year; closed only on December 25.
They should be open. Check the website though for any possible closures.
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