Elbridge Colby and Austin Long writing in The National Interest.
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. Regular U.S. strikes on North Vietnam over a period of seven years under highly favorable international conditions failed woefully either to convince Hanoi to change its fundamental strategy or substantially degrade the communist war effort. The North Vietnamese resolutely repaired bridges, depots and roads. More recently, limited allied air strikes against Iraq in the 1990s didn’t force Saddam Hussein’s compliance with UN Security Council Resolutions. Moreover, as happened in Vietnam, such strikes likely would become more difficult over time. The Russians, for example, have refrained, thanks to Western diplomacy, from selling Iran advanced long-range surface-to-air missiles that could make strikes more difficult. They probably wouldn’t be so forbearing if strikes were conducted without their prior and explicit approval, which Moscow isn’t likely to give.