Thanks to Trump and Bibi, America is in a position of choosing between a bad Iran deal and no deal. The first alternative reduces the danger of an Iranian bomb, but not to the extent that the previous deal did, and provides the regime with more resources to build ballistic missiles and support its allies in Lebanon, Syria, Yemen, and Iraq. The second alternative means there is no way to stop an Iranian bomb except war. There is no good choice here; which is worse?
The regime needs whatever money it can get to improve the lives of its citizens. Its ability to do mischief outside of its borders is constrained by the fact that the vast majority of Arabs are Sunnis. To my knowledge, its ballistic missiles will have difficulty penetrating Israel’s Iron Dome system. On the other hand, an Iranian bomb might cause MBS to want one of his own, and God knows what happens after that. In addition, it would call Israel’s ability to intervene in Lebanon and Syria into question, as the Iranians could plausibly put their allies under their new nuclear umbrella. Finally, a war to stop the bomb would be exactly what America doesn’t need at a time when we should be focusing on containing Putin and Xi.
On balance, I would say the no deal option is worse, although I would concede that reasonable persons could differ on this issue. One thing is for sure–Biden has no incentive to make the decision until after the election, particularly in light of the illness of the Supreme Leader and the new unrest in Iran.