If the views people espouse are illegal, then punish them via the law.
What about illegal activities outside of the law's jurisdiction?
>>If the views people espouse are illegal, then punish them via the law.
This also goes for their activities.
There is a clear difference between someone saying "I think Terrorist Group X is great" on twitter and someone using their bank account so that Terrorist Group X can buy stuff to make bombs. And even in that latter case, once the person concerned has finished their prison sentence they should still get a bank account so they can live.