Austin Long and Elbridge Colby pinpoint strike supporters' inability to define an endgame:
The basic question is: How do attack advocates propose to stop the Iranian nuclear program if Tehran refuses to roll over after one round of attacks? There are two logical responses to this question. One is regime change, presumably through invasion. But there are significant downsides to invasion, not least that such a war would likely prove protracted and costly. Attack advocates such as Kroenig effectively concede that the American people are unlikely to support this course.
The other is that the United States should be prepared to conduct repeated strikes over a long period of time to ensure the Iranian nuclear program is kept down. Unsurprisingly, Kroenig and others shy away from this answer, as it is a recipe for perpetual war.
The cost in lives, resources and America’s international reputation would be formidable, especially if done without diplomatic cover and international support that probably wouldn’t be forthcoming. Yet, even under the most favorable conditions in which Iranian retaliation stayed limited and international support was forthcoming, a long-term, limited-strike campaign might not work at a level of effort and damage in line with U.S. aims.
Goldblog is on the same page (follow-up here). Anne-Marie Slaughter proposes an international diplomatic initiative to prevent the US and Iran from driving each other over a cliff. My view is that containment and MAD is the only practical endgame, until the regime collapses. As, just like the Soviet Union, it will.