I don't really mind this-- indeed I guess I'm for it-- provided it's more or less symbolic. Restricting people's rights to speak other languages, besides being blatantly unconstitutional, would obviously be horrific. I've always felt there's something a bit weird in putting official documents, such as ballots, in foreign languages, but I don't really object to it, and am not particularly inclined towards preventing people from accessing government services or exercising their rights; anyways, that's a matter for the states.
If we had parts of the country where immigrants could live for generations without ever even learning English, that might be an concern, but history shows that such things don't really persist in that way and communities integrate in a fairly short amount of time.
I agree everyone should speak English, and should really try to do so, but I can empathise with those who cannot-- learning a new language is hard, especially when older. I can no longer bring myself to mock or complain about anyone's poor English when I know my French is almost certainly worse.
So a one line page, fine. Even then I'd be concerned people would take such a law as a license to harangue others for not speaking English, and it's hard to see such a law could serve as effective red meat without provoking such a response. Anything more than that would probably be, well, problematic.
Yeah, something symbolic would be nice. A message that if you want to live in America, you need to learn English. Or at the very least, don't expect others to speak your language or understand you. While this is not a problem in most of the country, there is some expectation on the part of a few in Southern California that everyone should understand Spanish. I especially feel bad for Hispanics who don't know Spanish. They really get a bad attitude from some people.
I also say this as an immigrant who speaks two other languages besides English. I don't want to restrict anyone's ability to speak another language. I don't have anything against people learning multiple languages (voted yes on proposition 58). Indeed, that is a good thing. There just shouldn't be an expectation that anyone needs to know any language other than English to go about their day in this country. I also hate Trump, as an FYI. I just think if he is going to do something draconian, this would be better than deporting 12 million humans.