What to know about the U.S. B-2 stealth bomber used against Iran's nuclear sites

Open this photo in gallery: A B-2 stealth bomber on a runway in Palmdale, Calif., in 2014. The U.S. has used its B-2s in seven wars, including the Iran attack on Saturday.FREDERIC J. BROWN/AFP/Getty Images It was a sneaky and surgical strike: a massive show of force with a weapon that remains the envy of military powers around the world. On the weekend, the United States attacked nuclear sites deep underground in the remote mountains of north-central Iran. It began when the U.S. Air Force launched a group of B-2 stealth bombers from Whiteman Air Force Base in Missouri and…