Iran claims it is capable of building a nuclear weapon as Supreme Leader Ayatollah Ali Khamenei vows a 'tooth-breaking' response to Israel and the U.S. A top adviser to Khamenei warns that Iran may alter its policies on using nuclear weapons if faced with an existential threat. General Mohammad Naeini of the Iranian Revolutionary Guard promises a decisive and strong response to enemy aggression. Israel's attack on Iran's military infrastructure on Oct. 26 was in response to missiles launched from Iran into Israel on Oct. 1. There are concerns that Iran's retaliatory strike could come at any time.