Iran also faces a possible attack on its nuclear program by Israel, potentially with the support of the United States, which has said Tehran cannot be allowed to acquire nuclear weapons something it has has denied trying to do.Iran’s Supreme Leader Ayatollah Ali Khamenei has warned that if the U.S. or any other nation acts against Iran, they will “receive a severe blow.” His remarks, delivered in a televised speech and amplified on official social media, come as tensions escalate between Washington and Tehran.The warning follows U.S. President Donald Trump’s statement on Monday that Iran would be held responsible for Houthi attacks. What is the worst that can happen to Iran ?