Especially since this month's midterm election gains by Republicans in Congress, President Obama has been getting much public advice to make sure Iran understands that a military strike against it is a credible threat. That can't hurt, but it misses the point.
My friend Nir Boms published a new piece on Iran, showing how Iran's economy is starting to go critical. Whether by sanctions or domestic policies, Iran's decline points up an important reality about that country's illicit nuclear program (and one with which Nir may or may not agree).
As much as Americans and Israelis may hope for a military strike that miraculously takes out Iran's far-flung and dug-in facilities, this would actually be the best boost for Iranian President Mahmoud Ahmadinejad and his clerical backers. Iranian public opinion is clearly slanted against him, which is why he had to rig last year's election. Following his crackdown on post-election demonstrators and opposition leaders, and with daily life impacted by economic misery, a "Zionist" attack would be his deus ex machina.
If Iran does get too close to achieving a dangerous nuclear capability, a military strike may be unavoidable, given the costs of inaction. In the meantime, though, the Iranian regime is unlikely to abandon the nuclear program on its own (nor will it allow open inspections). The sanctions will not convince the regime, but they are definitely depriving the regime of capital and public support.
Whether the Islamic Republic runs out of money first, or is somehow overthrown (which wouldn't by itself end Iran's nuclear program), our default strategy should be to DEPRIVE the regime of its capacity to continue, not to CONVINCE it.
Iran is not the Soviet Union, and not only because it is not a rational, predictable actor. The existential threat Soviet ICBMs once posed to the United States was two orders of magnitude above the hypothetical threat posed by a nuclear-armed Iran. Mutually Assured Destruction and nuclear deterrence theory are poor guides to dealing with today's Islamic Republic and its opportunistic regional ambitions.
In the end, Iran will not be deterred by the threat of a military strike, no matter how credible or severe. Iran's quest can only be denied, whether by the impact of economic weapons or by an actual military strike.
The most important mission of the military planning on Iran is to mean business, not to "look" like we mean business.