He can and he will.
It will be by order or priority. People who have committed crimes above and beyond entering America and then go down the list.
If I were Trump, I would honestly offer an olive branch to any of these citizens who enter America (assuming they haven't committed any other crime in addition to entering America) and who sign up or are willing to sign up for the U.S military. Perhaps offering them a path to citizenship, over a period of a few years, but much quicker than others.
To me that would suggest they are willing to risk their lives for America and worth keeping. Courage is the greatest attribute a society can have and worth protecting.