I don't think it's about race. I think it's about anti-Americanism and those who try to enter this country illegally.
It's difficult to see it about anything
other than race, hypocrisy, and short-term political gain.
Trump was born in the US; his father was born in the US; his mother was born in Scotland. His own American roots don't go very deep. He also made a career about attacking and denigrating the US, and complaining about government policies he doesn't like.
As noted, three of the four women in "The Squad" were born in the US. Ayanna Pressley's family has been in the US for generations. AOC's father was born in the US, and her mother in Puerto Rico (which means she's a natural born American citizen). Rashida Tlaib was born in Detroit. It is only Omar who is a naturalized citizen.
He hasn't used this kind of attack on any whites, such as Nancy Pelosi (1st generation born in US from her family), Bernie Sanders (1st gen), Joe Biden (2nd Gen) etc.
And of course, it's not like this is coming out of the blue. Trump has a
long history of racist actions and statements.
As hinted above, the hypocrisy is not just about how
so many of the nativists in political positions/office are descendants of refugees, chain migrants, illegal immigrants, economic migrants, immigrated during a period of open borders, and so on. It's that conservatives routinely criticize and attack the US, yet state that anyone of any other political view (centrists, leftists etc) who does the same must "hate America" -- even though
almost all domestic terrorism now is right-wing, and violence on the extreme right is growing.
And of course, the political angle is absurdly transparent. Trump saw that "The Squad" and Democrats were getting lots of press over policy disputes. Since he can't stand for anyone else to be in the spotlight, he jumped into the fray in order to monopolize the attention and whip up his base.
Apparently it doesn't matter that these kinds of tactics backfired in the 2018 elections; or that in the long run this can only hurt conservatism and the Republican party, which will be tarred with this kind of anti-minority sentiment for decades. As a reminder,
the non-white population is growing, especially in "Red" states like Texas and Georgia, and swing states like Florida. Smooth move, Ferguson...