Iran’s supreme leader, Ayatollah Ali Khamenei, is taking precautions against assassination, according to three Iranian officials familiar with his emergency war plans. He speaks with his commanders mostly through a trusted aide now, the officials said, and electronic communications have been suspended to make it harder to find him. He has also chosen replacements for his lieutenants down the chain of military command, in case of their deaths. The chief of staff of Iran’s armed forces and senior military commanders have been killed in the conflict., The United States bombed three nuclear sites in Iran on Saturday, bringing the U.S. military directly into Israel’s war with Iran, a move that could kick off a more dangerous phase in the war. The attack followed days of uncertainty about whether Mr. Trump would intervene in the conflict, which began with a surprise attack on Iran by Israel , Iranian-backed Houthi rebels in Yemen said they would resume attacks on U.S. vessels and warships in the Red Sea if the Trump administration joins Israel’s military campaign against Iran..