Iran has their terrorist group proxies throughout the region. I think there's some truth to this, although the actions of some truly rogue terrorist groups probably get blamed on Iran because it's been the zeitgeist for a few decades to find reasons to attack Iran.

Whatever the case, the current Iran regime hasn't given nuclear material, chemical weapons, or biological weapons to these terror groups.

If the current Iran regime is eliminated from afar, with some fly-by bombings or whatever, what happens in the chaos that follows? Nuclear material and other weapons do not poof out of existance when the government that created them falls. Which group will control the nuclear material going forward? Roll the dice to find out.