The stronger you build your safety net, the higher you build your castle walls and the deeper you dig your moats.
I'd caught this one last week, but it's now made international news. A top mathematician's abandoned his post at Auckland Uni because Immigration New Zealand didn't like the costs his autistic son might someday impose on the State.
The Twitter left has been rightly outraged, but they're misdiagnosing the problem. Yes, in a first-best infinite-resource world, the government wouldn't be worried about this and would just let him stay. And even in just a saner version of the existing world, the government would recognise that the family is going to be strong net taxpayers on the top marginal tax rate and waive the son in.
But the real underlying problem is that safety nets build moats and walls. Maybe there could have been a sane workaround for this guy. But what about the desperately poor person abroad who could be just a little bit poor here, working on the minimum wage? He'd be massively better off by moving. But there's risk of needing welfare, there'd be transfers through WFF, and nobody likes having poorer people in visible places. So they're on the other side of the moat and wall, to avoid potential burdening of the net.
Nets don't just support. They constrain and bind. It's easy to ignore the tradeoff, but it doesn't make it less real.