Alexandra, you're forgetting a few things:
1. Most immigrants aren’t Muslims—and Muslims are the problem.  The Quran is a manifesto for violence--please read it.  (And often it’s the 2nd generation that’s the real problem, as we’ve learned in the UK.)
2. We’re not talking about ‘crimes’, which includes everything from shoplifting to joyriding and so on, but about acts of terrorism.
3.  The fact that American citizens commit crimes (including, rarely, terrorism, eg James Hodgkinson)  is no reason to make things worse by permitting entry to potential terrorists.

Do you think the US was wrong to ban entry to Communists during the Cold War?  Don’t governments have a duty to protect their citizens?