Israel (now broader Mid East discussion)

They may not be some monolithic block, and this guy may be just a vocal minority, but there are significant numbers of migrants who migrate to countries, who do not appreciate the culture or societal norm of those countries. Are they going to stage a rebellion? Probably not. Could situations present themselves such as 9/11, the Paris attacks of 2015, the Madrid train bombings in 2004? Yes.

You live in the UK, right? I am sure you know that Heathrow is always on high alert due to the possibility of terrorist attacks.
Feels like you're being disingenuous here with this "they may not be some monolithic block", because I'm 99.9% sure you know they're not a monolithic block and that radical extremists are a minority,

Also citing 'Heathrow being on high alert'? We have quite the history of terrorism here. It's not new. We had things like the Manchester Arena bombing in 2017, and the 7/7 central London bombings, carried out by Islamist extremists, were in 2005. Then there have been things like the bomb attacks in Warrington, where I live, in 1993. Of course, that one was the IRA. We've also had the murder of an MP and attacks carried out by white nationalists in recent years.

See, people have been opposing radicalism, from every source, this whole time. At no point has anyone gone, "Hey, these radical terrorist attacks, they're alright! Let's tolerate them and the extremist philosophy behind them!" That's never been a thing. Counter-terrorism and deradicalisation programs have been in place for decades.

And one of the things that comes out of that is understanding that one of the drivers of radicalism is prejudice and bigotry. Like, step one of trying to radicalise someone is telling them that the rest of the country will never accept them, that they hate people who look like them, etc., etc.

So lumping people who aren't radicalist extremists in with those who are, saying or implying they lack essential human values, or that they're all potential terrorists and should be deported, isn't a great way to fight terrorism, it's a great way to help radicalist extremists in their efforts to recruit them. Which is one reason why I really hate to see it.