Technically correct, but I guess it depends on context, both cultural and conversational. In the UK for example, "America" and "American" always refer to US not the continent, unless there's specific context surrounding it to suggest otherwise. I believe that's generally the case in the US as well, and I suspect (but could be wrong) in most countries?
I think it's technically incorrect, actually. In standard English, American is the demonym used to refer to citizens of the USA.
People seem to make a number of wrong assumptions on that, including 1) it can't also be the demonym for anyone else and 2) other countries can decide another countries demonym in their native language. Both of these things are patently false. If someone wants to use American to refer to a member of the Americas (continents) then they certainly can, but they should include enough context to disambiguate. Moreover, other nations don't decide what a nation gets to call itself in its native language. We call ourselves Americans -- so we are Americans. If other countries don't like that, well, tough for them.
