From the start, Adams’s presidency was in crisis. France retaliated for the British-friendly Jay Treaty by abandoning its 1778 alliance with the United States. French privateers—armed private vessels—started detaining American ships carrying British goods; by March 1797, more than three hundred American vessels had been seized. To avenge these insults, Federalists started murmuring openly about war with France. Adams preferred negotiations and dispatched a three-man commission to France in the fall of 1797. But at the same time, he asked Congress to approve expenditures on increased naval defense.

When the three American commissioners arrived in Paris, French officials would not receive them. Finally, the French minister of foreign affairs, Talleyrand, sent three French agents—unnamed and later known to the American public as X, Y, and Z—to the American commissioners with the information that $250,000 might grease the wheels of diplomacy and that a $12 million loan to the French government would be the price of a peace treaty. Incensed, the commissioners brought news of the bribery attempt to the president.

Americans reacted to the XYZ affair with shock and anger. Even staunch pro-French Republicans began to reevaluate their allegiance. The Federalist-dominated Congress appropriated money for an army of ten thousand soldiers and repealed all prior treaties with France. In 1798, twenty naval warships launched the United States into its first undeclared war, called the Quasi-War by historians to underscore its uncertain legal status. The main scene of action was the Caribbean, where more than one hundred French ships were captured.

There was no home-front unity in this time of undeclared war; antagonism only intensified between Federalists and Republicans. Because the chance of a land invasion by France seemed remote, some Republicans began to fear that the Federalists wanted that enlarged army to threaten domestic dissenters. Adams’s cabinet strenuously backed the army buildup, making the president increasingly mistrustful of their advice. He was beginning to suspect that his cabinet was more loyal to Hamilton than to himself.

Party antagonism in the realm of public opinion spiraled out of control. Republican newspapers heaped abuse on Adams. One denounced him as “a person without patriotism, without philosophy, and a mock monarch.” Pro-French mobs roamed the streets of Philadelphia, the capital, and Adams, fearing for his personal safety, stocked weapons in his presidential quarters. Federalists, too, went on the offensive. In Newburyport, Massachusetts, they lit a huge bonfire and burned issues of the state’s Republican newspapers. Officers in a New York militia unit drank a menacing toast on July 4, 1798: “One and but one party in the United States.” A Federalist editor ominously declared that “he who is not for us is against us.”