Regime change: the legacy: since 1953, U.S. presidents have been toppling other governments. Now, the consequences.(Special report: the foreign policy crisis)

A very happy group of men convened at the White House on Sept. 4, 1953, to hear a cloak-and-dagger story that would resonate through all of subsequent American history. Two weeks before, the Central Intelligence Agency had overthrown Prime Minister Mohammed Mossadegh of Iran. It was the first time the CIA had deposed a foreign leader, and on this day the agent who ran the operation, Kermit Roosevelt, was to explain how he did it.

Roosevelt's account of bribes, staged riots and artillery duels was almost too hair-raising to believe. It transfixed everyone in the room, including President Dwight Eisenhower, who later wrote that it "seemed more like a dime novel than historical facts." If there was a single moment when the United States can be said to have entered the modern era of covert action and regime change, this was it.

"One of my audience seemed almost alarmingly enthusiastic," Roosevelt later recalled. "John Foster Dulles was leaning back in his chair. Despite his posture, he was anything but sleepy. His eyes were gleaming; he seemed to be purring like a giant cat. Clearly he was not only enjoying what he was hearing, but my instinct told me that he was planning as well."

Roosevelt's instinct was true. Soon after his triumphant White House briefing, his CIA superiors approached him with a new offer. President Eisenhower and Secretary of State John Foster Dulles wished to be rid of troublesome Guatemalan leader Jacobo Arbenz. Seeing as Roosevelt had already shown his skill at toppling elected governments, would he like to try again? He demurred, but the project went ahead anyway. It was another brilliant success, as Arbenz was forced from power and replaced by a pliant colonel. In the space of less than a year, the CIA had de posed two popular leaders whose nationalism and refusal to accommodate foreign capital had made them anathema in Washington.

These two "regime change" operations set the United States on a course to which it still holds. Over the 50 years that have followed, driven by a combination of idealism and arrogance, successive American administrations have assumed the right to topple governments around the world. Only now, in the wake of the shocks that the world system has suffered in the last few years, is the …