T of how far America has set back Iran’s nuclear programme clearly matters. That can be far less certain of any of the answers America is coming up with. While the strikes on Iran showed the supremacy of American air power, they also may have revealed a weakness in its national security. According to Donald Trump, the country’s spy agencies failed before the assault in a critical mission, assessing the threat posed by Iran’s nuclear programme. Mr Trump’s claim should heighten doubts now about...