 Complete the following phrase:  In the aftermath of the invasion, Carter was determined to respond vigorously to what he considered a dangerous provocation. In a televised speech, he announced sanctions on the Soviet Union, promised renewed aid to Pakistan, initiated renewed registration for the Selective Service System, and committed the U.S. to the Persian Gulfs defense. He imposed an embargo on grain shipments to the USSR, tabled consideration of SALT II, and requested a 5 annual increase in defense spending. Carter also called for a boycott of the 1980 Summer Olympics in Moscow. British prime minister Margaret Thatcher enthusiastically backed Carters tough stance, although British intelligence believed the CIA was being too alarmist about the Soviet threat to Pakistan. The thrust of U.S. policy for the duration of the war was determined by Carter in early 1980: Carter initiated a program to arm the mujahideen through Pakistans ISI and secured a pledge from Saudi Arabia to match U.S. funding for this purpose. U.S. support for the mujahideen accelerated under Carters successor, Ronald Reagan, at a final cost to U.S. taxpayers of some 3 billion. The Soviets were unable to quell the insurgency and 