The president of the Council on Foreign Relations has an idea:
Instead of threatening to leave JCPOA, a muscular Iran policy would include helping Kurds resisting Iran-backed governments in Iraq, Syria
— Richard N. Haass (@RichardHaass) October 16, 2017 
If the U.S. were to do that, it would make a dangerous situation much worse. By “helping Kurds” to resist “Iran-backed governments,” I assume Haass means at the very least providing them with arms and logistical support so that they wage war against the government in Baghdad. Leave aside for the moment how this ignores the political divisions among different Kurdish groups and oversimplifies Iran’s relationships with the Iraqi and Syrian governments, and just marvel at the knee-jerk stupidity of the proposal.
It isn’t clear how far Haass wants this “muscular” policy to go, but it would seem to commit the U.S. to back Kurdish insurgents against at least two governments (one of which we have armed and supported for over a decade) plus Iran and its proxies and probably Turkey as well. This would stoke a conflict that the U.S. should be trying to stop, it would expose U.S. forces to retaliation from some or all of these governments, and it would gain us nothing except an open-ended conflict that serves no discernible purpose except to create mayhem. On top of all that, it would probably improve Iran’s position in the region by giving its neighbors common cause to cooperate with them against a U.S.-backed insurgency.
I doubt that Haass’ proposal will be adopted, if only because I don’t think Secretary Mattis would be stupid enough to endorse it, but it is alarming that this is what passes for clever policy advice from one of the pillars of the foreign policy establishment in response to a new conflict. Less than 24 hours after the eruption of fighting between Kurdish forces and the Iraqi government, we are already hearing proposals from high-profile people to throw weapons at the problem for the sake of hurting Iran. It was the same reflexive “do somethingism” and hostility to Iran that inspired the last five years of disastrous meddling in Syria, and Haass would like to apply the same lousy ideas to Kurdistan as well. I don’t see how this “muscular” policy would be anything but a debacle for the U.S., and it would probably prove to be a nightmare for the Kurds.