[a]
On October 6, 1973, an Arab coalition led by Egypt and Syria, supported with arms and materiel by the Soviet Union, attacked Israel in the Yom Kippur War. Israel suffered heavy losses and Nixon ordered an airlift to resupply Israeli losses, cutting through inter-departmental squabbles and bureaucracy and taking personal responsibility for any response by Arab nations. More than a week later, by the time the U.S. and Soviet Union began negotiating a truce, Israel had penetrated deep into enemy territory. The truce negotiations rapidly escalated into a superpower crisis; when Israel gained the upper hand, Egyptian President Sadat requested a joint U.S.–USSR peacekeeping mission, which the U.S. refused. When Soviet Premier Brezhnev threatened to unilaterally enforce any peacekeeping mission militarily, Nixon ordered the U.S. military to DEFCON3,[183] placing all U.S. military personnel and bases on alert for nuclear war. This was the closest the world had come to nuclear war since the Cuban Missile Crisis. Brezhnev backed down as a result of Nixon's actions.[184]
Because Israel's victory was largely due to U.S. support, the Arab OPEC nations retaliated by refusing to sell crude oil to the U.S., resulting in the 1973 oil crisis.