I'm more interested in how you interpreted it. There are two possible ways you can answer, and choosing either means you were wrong in at least one way.
If unAmerican does not have any objective definition, and is instead a rhetorical device used to fallaciously attack opposing opinions, it follows that you should apologize for employing it, and sinking to the level of Trump.
If unAmerican does have an objective definition, then that definition must mean "unconstitutional," as that is what you have asserted the meaning is. Unless, of course, you admit to using the term incorrectly.
If you were intending to only provide your interpretation of the term, then you have implicitly provided support for the idea that the term is inherently subjective, and have contradicted your own implications here and elsewhere.
Please clarify your position and intentions. Thank you.