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Romney: If I were Iran, if I were Iran—a crazed fanatic, I'd say let's get a little fissile material to Hezbollah, have them carry it to Chicago or some other place, and then if anything goes wrong, or America starts acting up, we'll just say, "Guess what? Unless you stand down, why, we're going to let off a dirty bomb." I mean this is where we have—where America could be held up and blackmailed by Iran, by the mullahs, by crazy people. So we really don't have any option but to keep Iran from having a nuclear weapon.

Romney didn't appear to understand that a dirty bomb—an explosive device that spreads radioactive substances—does not require fissile material from a nuclear weapons program. Such a bomb can be produced with, say, radioactive medical waste. If Iran's nuclear program poses a threat, it is not because this project will yield a dirty bomb.

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