"I doubt very much our ability to manage some of the consequences," says Mr. Ranstorp, noting that Iranian revenge attacks in the past have been marked by "plausible deniability" and have had global reach.
"If you attack Iran you are unleashing a firestorm of reaction internally that will only strengthen revolutionary forces, and externally in the region," says Ranstorp. "It's a nightmare scenario for any contingency planner, and I think you really enter the twilight zone if you strike Iran."
Though the US military has since early 2007 accused Iran's Qods Force – an elite element of the Islamic Revolutionary Guard Corps (IRGC) – of providing anti-US militias in Iraq with lethal roadside bombs, and of training and backing "special groups" in actions that the US government alleges have cost "thousands" of lives, US commanders have played down Iran's military capabilities.
Even Admiral William Fallon, who publicly opposed a US strike on Iran before he resigned in April, dismissed Iran as a military threat. "Get serious," Adm. Fallon told Esquire in March. "These guys are ants. When the time comes, you crush them."
But that has not kept Iran from rhetorical chest-beating, with an active military manpower of 540,000 – the largest in the Middle East – dependent on some of the lowest per capita defense spending in the region. Iran "can deal fatal blows to aggressor America by unpredictable and creative tactical moves," the senior commander Brig. Gen. Gholam Ali Rashid said in late May. "It is meaningless to back down before an enemy who has targeted the roots of our existence."