Romney echoed his rhetorically hawkish GOP foes.
"With crippling sanctions and a very clear statement that military action is an action that will be taken if they pursue nuclear weaponry," Romney said. "That could change the course of world history."
Only Texas Rep. Ron Paul, a fierce Libertarian, stood on the debate stage and spoke against a preemptive strike against Iran's nuclear weapons program. Paul said there are moral and constitutional impediments that should prevent a U.S. attack on Iran—not to mention to potential costs.
"Al Qaeda has had a plan to bog us down in the Middle East and bankrupt this country," Paul said. "That's exactly what they're doing. We've spent $4 trillion of debt in the last 10 years being bogged down in the Middle East."
The Congressional Research Service has calculated the Iraq war, launched under Bush's doctrine of preemption, cost over $800 billion; the Obama White House puts the tab at $1 trillion.
Suri said while politics is at surely at work in the candidates' muscular rhetoric on Iran. But he also sees "serious people in the Republican establishment that believe there are regimes in the world that are irreconcilable to American interests and the only way to deal with them is to eliminate them."