2004 article in The Atlantic
Will Iran Be Next? Soldiers, spies, and diplomats conduct a classic Pentagon war game—with sobering results
So this is how the war game turned out: with a finding that the next American President must, through bluff and patience, change the actions of a government whose motives he does not understand well, and over which his influence is limited. "After all this effort, I am left with two simple sentences for policymakers," Sam Gardiner said of his exercise. "You have no military solution for the issues of Iran. And you have to make diplomacy work."
http://www.theatlantic.com/magazine/archive/2004/12/will-iran-be-next/303599/