Michael Ledeen believes that the Iranians bombed the African embassies. He thinks that the Iranians controlled Zarqawi. He is basically not credible.

An air war would be disaster, but an insurgency/revolution supported by the United States would be somehow cost-free? I find it difficult to believe that the Iranian regime would not respond ferociously at any genuinely serious attempt to undermine it, which indeed it likely believes the U.S. is engaged in right now.

Seeing the Iranian government as a unified conglomerate bent on "world domination" is remarkably inaccurate. To project an eschatalogical worldview upon the entire Iranian leadership is equally silly. The Iranian clerical leadership is divided not only by worldview but also serious institutional and material interests. Iran is an authoritarian state, but it is not a totalitarian dictatorship like Iraq or North Korea --- it has a functioning system with multiple and competing centers of power, some of which are radical and others which are less so.