Iran

As the full suite of American sanctions, including penalties on importing Iranian crude oil, snap back into place, Iran's precarious economic situation will certainly deteriorate.

This announcement is a visceral blow to Iran’s dignity, and no serious politician would survive an effort to engage with the Trump administration at this time.

[The Europeans] will engage in a "period of frantic diplomacy" before sanctions come into effect to see what, if anything, can be preserved.

If [President Trump is] convinced the restrictions imposed were insufficient, or the monitoring of the [Iranian] regime was insufficient, how does the absence of these measures and restrictions provide greater security for the U.S.?...I would interpret [withdrawing from the JCPOA] as an ego move. It played to his own sense of identification as sort of the master of the deal, even at the risk of a global calamity.

The [Iran nuclear] deal isn't a treaty. It's an international political agreement. That means the U.S. voluntarily bought into it, and it doesn't necessarily mean the whole thing falls apart. One of the peculiarities of the agreement [is that it] does not include mechanisms for withdrawal.