TEHRAN, April 8 -- Airstrikes pounded Tehran on Tuesday, and Iranian officials urged young people to form human chains to protect power plants, hours before the expiration of US President Donald Trump's latest deadline for the Islamic Republic to reopen the crucial Strait of Hormuz or face punishing strikes on its infrastructure. Trump has extended previous deadlines but suggested the one set for 8 p.m. in Washington was final, and the rhetoric on both sides reached a fever pitch, leaving Iranians on edge. P10...