Could a Strike on Iran Spark a Nuclear Explosion? Brian Palmer: Sorry, nuclear weapons don't detonate like that By Neal Colgrass, Newser Staff Posted Mar 17, 2012 6:06 PM CDT 14 comments Comments A nuclear mushroom cloud: not what would occur after a missile strike on Iran's nuclear plants. (Shutterstock) (Newser) – As pressure mounts for a US or Israeli strike on Iran's nuclear facilities, you may be wondering whether such an attack would trigger a mushroom cloud or cause dangerous materials to leak. Brian Palmer lays those fears mostly to rest in Slate, saying Iran probably hasn't enriched enough uranium to build a weapon—and even if it has, a missile strike that hits a nuclear weapon almost certainly wouldn't start a chain reaction. Why? A nuclear bomb is designed to set off carefully choreographed internal explosions that detonate the weapon, causing compressed uranium to explode. But a missile strike on a stored nuclear weapon is far more likely to mess up its chain reaction than trigger it, Palmer explains. An attack might cause gaseous uranium to leak out of a facility, he concedes, but because the uranium is not reacted, it probably wouldn't cause radiation sickness. For all the scientific details—and a "bonus explainer" on whether a gun can set off a conventional bomb—see the full article here .