The outbreak of the French revolution coincided with the beginning of George Washington's first administration, but by 1793, warfare had engulfed Europe, pitting England, Prussia, Austria, and Spain against the new French Republic.
In the cabinet Thomas Jefferson opposed any expression of neutrality while Alexander Hamilton supported it. Washington eventually sided with the latter and issued a proclamation of neutrality that barred American ships from supplying war matériel to either side. The proclamation stated that the United States would not offer protection to Americans who violated neutrality laws, and that the United States would actively prosecute anyone within its jurisdiction who violated international law with respect to neutrality.
The issue was very sensitive. The United States had won the War of Independence largely through the military and financial support of France, but that was before the French Revolution. Hamilton and his fellow "aristocratic" supporters were not in symnpathy with the revolution. Their argument, which ultimately persuaded Washington, was that France had helped in a war in which they had an interest in the outcome. France's new war was entirely of a European nature and the United States had no interest. Hamilton said as much in newspaper articles written under the name "Pacificus". In the third Pacificus letter, he suggested that France was not due American support since she had to a degree brought the situation on herself.
Jefferson and his adherents, to the contrary, were inspired by the revolution and felt that neutrality was a betrayal. Jefferson wrote to Hamilton that:
I consider the people who constitute a society or nation as the source of all authority in that nation, as free to transact their common concerns by any agents they think proper, to change these agents individually, or the organisation of them in form or function whenever they please: that all the acts done by those agents under the authority of the nation, are the acts of the nation, are obligatory on them, & enure to their use, & can in no wise be annulled or affected by any change in the form of the government, or of the persons administering it.
It was a good argument, based on the same principle that the U.S. Constitution was instituted by "the people." However, there was nothing to gain and much to lose for the United States to involve itself in a European conflict, and whether from Hamilton's logic or the clear national interest, Washington opted for neutrality.