The U.S. is now flying B-52 bombers over Iran — an operational shift that signals American forces have achieved air superiority inside parts of the country after weeks of strikes degraded Tehran’s defenses. Chairman of the Joint Chiefs of Staff Gen. Dan Caine said in a briefing Tuesday the missions began "given the increase in air superiority," as U.S. forces expand operations inside Iranian territory. President Donald Trump said during an address to the public Thursday night that Iran’s air defenses had been "annihilated," calling U.S. forces "unstoppable." "We are in this military operation … for 32 days," he said. "And the country has been eviscerated and essentially is really no longer a threat." TRUMP SAYS IRAN ‘NO LONGER A THREAT’ AFTER 32 DAYS — OUTLINES NEXT PHASE OF US WAR The bomber, first used during the Cold War and flown for about 70 years, allows the U.S. to expand the pace and flexibility of its strikes.…