France is nearly 9% Muslim. Outside the large cities, it isn't apparent, to me anyway. The wife tells me Marseilles is heavily Muslim, which makes some sense. I have not yet been there. That's the only larger city in France I have not visited. There is a dude visiting here from there who says he likes it, he's a math professor at the university there, he comes here often to collaborate with GaTech. He's not Muslim, doesn't like Muslims, as he's gay.
The US is something like 1% Muslim. And yes, at times, some of them commit extremist acts.