Hizbullah's leader said Tuesday that any US attack on his patron Iran would be "the biggest folly" in American history. Sheik Hassan Nasrallah's comments came as US President George W. Bush toured the Middle East on a trip used in part to drum up Arab opposition against Iran, which Bush called "the world's leading state sponsor of terror." Responding to Bush, Nasrallah said Iran would defend itself against any US attack. "If America launches a war against Iran, it will be the biggest folly committed by America in its history," the black-turbaned cleric said in a speech broadcast on a giant screen in front of thousands of supporters in downtown Beirut. Nasrallah suggested that if the US attacked Iran, there would be such a backlash that American interests in the region would be destroyed. "Who said that a war on Iran will achieve America's expectations?" Nasrallah asked. Nasrallah also warned against a worsening humanitarian situation in the Gaza Strip, saying Bush's visit to Israel had empowered the Jewish state to wreak havoc in Palestinian areas.