"He does badmouth _illegal_ immigrants, true"
So which is it?
It really doesn't matter though, as the point is that he is putting the blame on others (immigrants, other countries and their trade practices, etc.). Whether the immigrants are "illegal" or not doesn't matter in this context: it's an out group that grievances can be directed towards.
I'd be remiss if I didn't leave this here:
“Allowing the immigration to take place in Europe is a shame,” Trump said. “I think it changed the fabric of Europe and, unless you act very quickly, it’s never going to be what it was and I don’t mean that in a positive way.
“So I think allowing millions and millions of people to come into Europe is very, very sad,” he continued. “I think you are losing your culture. Look around. You go through certain areas that didn’t exist ten or 15 years ago.”
https://www.washingtonpost.com/news/politics/wp/2018/07/13/t...