"Presidents Make Decisions Based on Intelligence."
Not the big ones. From George W. Bush trumpeting WMD reports about Iraq to this year's Republican presidential candidates vowing to set policy in Afghanistan based on the dictates of the intelligence community, Americans often get the sense that their leaders' hands are guided abroad by their all-knowing spying apparatus. After all, the United States spends about $80 billion on intelligence each year, which provides a flood of important guidance every week on matters ranging from hunting terrorists to countering China's growing military capabilities. This analysis informs policymakers' day-to-day decision-making and sometimes gets them to look more closely at problems, such as the rising threat from al Qaeda in the late 1990s, than they otherwise would.
On major foreign-policy decisions, however, whether going to war or broadly rethinking U.S. strategy in the Arab world (as President Barack Obama is likely doing now), intelligence is not the decisive factor. The influences that really matter are the ones that leaders bring with them into office: their own strategic sense, the lessons they have drawn from history or personal experience, the imperatives of domestic politics, and their own neuroses. A memo or briefing emanating from some unfamiliar corner of the bureaucracy hardly stands a chance.
Besides, one should never underestimate the influence of conventional wisdom. President Lyndon B. Johnson and his inner circle received the intelligence community's gloomy assessments of South Vietnam's ability to stand on its own feet, as well as comparably pessimistic reports from U.S. military leaders on the likely cost and time commitment of a U.S. military effort there. But they lost out to the domino theory -- the idea that if South Vietnam fell to communism, a succession of other countries in the developing world would as well. President Harry Truman decided to intervene in Korea based on the lessons of the past: the Allies' failure to stand up to the Axis powers before World War II and the West's postwar success in firmly responding to communist aggression in Greece and Berlin. President Richard Nixon's historic opening to China was shaped by his brooding in the political wilderness about great-power strategy and his place in it. The Obama administration's recent drumbeating about Iran is largely a function of domestic politics. Advice from Langley, for better or worse, had little to do with any of this.
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