Why shouldn’t Iran have nuclear weapons? We do. What gives the U.S. and Israel a moral right to manufacture the ultimate weapons of mass murder, then deny another nation the right to do likewise? This isn’t moral authority, but bullying. It’s “might makes right,” the lowest common moral denominator.
If the U.S. had any true moral authority, we would begin dismantling our own weapons from hell, then challenge other nations to do likewise.