Pretty much. There is a “National Harbor” in Maryland which is a…real estate development? Well, it does have some boat parking too. But nothing is “officially” “national” about it.
There is a National Aquarium in Baltimore. Confusingly there was a now-defunct National Aquarium in Washington, D.C. According to Wikipedia, the two had no common origin. I say the one in D.C. had a more legitimate claim to “National” as it had some federal government roots.
Then there’s the Washington Nationals baseball team. And the Virginia neighborhood bogusly renamed “National Landing”.
So pretty much anything can call itself “national” if it wants to.