Former Central Commander John Abizaid, probably the military officer with the most specific knowledge of the region and its cultural and political dynamics, says war with Iran would be a disaster and that we could live with a nuclear Iran if we needed to. As Ezra Klein points out there’s been a large effort to convince people that all “serious” observers know that “all options are on the table” is the only viable strategy, but when you get down to it it turns out that almost nobody with expertise in the region or in the field of non-proliferation actually agrees with the conventional wisdom about this.
The issue, of course, is that there’s actually nothing conventional about the CW on Iran. Instead it’s a product of interest-group pressure, political cowardice, and general public ignorance. If anything, the hair-trigger posture and general atmosphere of tensions is making it harder to find a real resolution of the situation.