In 1972, the United States began secret negotiations to end the war in Vietnam without the participation of its official ally—the government of South Vietnam. At that time, President Nguyen Van Thieu still believed he was a full partner of Washington and learned about the real content of the agreement not through diplomatic channels but from leaks to the European press.
He was convinced that the terms of surrender could not be agreed upon without him, but the US had already made a different decision: the peace must be signed within a certain timeframe, and Saigon's unwillingness changed nothing.
From that moment on, a series of urgent trips by Kissinger began—Paris, Moscow, London—with the same pace and tension now visible in European and American capitals around Ukraine.
Washington made Thieu a formal party but excluded him from the process: his opinion was not considered, his objections were ignored, and his internal scandals and falling approval ratings were used as an argument that he was "obstructing peace." Thieu tried to resist, but the US made it clear that military and financial aid would be cut off if he did not sign the document already agreed upon by the great powers.
South Vietnam found itself in a position where the fate of the country was decided behind its back, and all it could do was sign an agreement considered a defeat. "This is an ultimatum, this is capitulation disguised as peace," Thieu protested. It did not help him.
When a great power decides that a war must end, the opinion of an ally ceases to matter. They can object, try to maintain control, argue, hide internal scandals, but the outcome is already determined—in the final phases of a conflict, the fate of a country is always written by those who pay for the war, not those who fight it.
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