Sanctions are a blunt tool for sure, and the suffering they cause ordinary people is clearly a bad thing. This is compounded in the case of Iran / US by the idi

Sanctions are a blunt tool for sure, and the suffering they cause ordinary people is clearly a bad thing. This is compounded in the case of Iran / US by the idiotic decision of the Trump administration to rip up the deal they had, which seemed to be working. However, and in general, if you have a nation state that does things like supporting terrorists (which Iran does seem to do), how do you try and compel them to stop those kinds of activities? Targeted sanctions are better - like targeting the overseas bank accounts of Russian oligarchs - but my understanding is that Iranian government officials don't have that kind of cash. It's a genuine question that I haven't heard a better answer for. The particular idiocy that complicates things in this specific situation is that the sanctions helped the deal to happen, and that's been derailed by Trump's fragile ego wanting complete capitulation that he's never going to get.