As a result of the XYZ Affair, the US Congress rescinds the Treaty of Alliance with France sparking the "Quasi-War".

The XYZ Affair was a political and diplomatic episode in 1797 and 1798, early in the presidency of John Adams, involving a confrontation between the United States and Republican France which led to the Quasi-War. The name derives from the substitution of the letters X, Y, and Z for the names of French diplomats Jean-Conrad Hottinguer (X), Pierre Bellamy (Y), and Lucien Hauteval (Z) in documents released by the Adams administration.