People in western nations are largely responsible for climate change. Someone in Syria won’t be flying around the world and buying new clothes all the time. But they will be the ones hit the hardest by climate change, so they will likely either die or become refugees trying to come to the west.
Also, a lot of our western wealth is based on exploitation of those nations (through colonialism and later capitalism or wars). So if westerners don’t want people from poor countries to come to the west they should help those nations to recover from that exploitation.
Furthermore we need to do these things, because a bigger influx of desperate migrants will steer western politics even further to the right. That’s never a great thing and will lead to more inequality and possibly the collapse of our democratic systems.
Finally to your point about migrants being more criminal. That is largely a result of worse economic circumstances and outlooks. Improve their chances and watch the crime rate drop.
We might have that here, but half the people I know work jobs that still expect them to be on call all the time and would get in serious trouble if they turned of their phones during busy periods. So while yes, in theory it’s great, our toxic work culture seems to cancel it out quite well.
I always tell those guys they should quit it or sue the fuck out of those assholes, but no one ever does -.-