The event during John Adam's presidency which could be said to have been the reason the Federalist Party began to fall apart was The Alien and Sedition Acts.
In 1798, four laws collectively referred to as the "Alien and Sedition Acts" were established, placing restrictions on immigration and free speech. The Sedition and Alien Acts caused controversy.
They were defended on the grounds that they enhanced national security during the Quasi-War, clandestine naval combat with France from 1798 to 1800, with the support of the Federalist Party. Democratic-Republicans denounced the moves as a violation of the First Amendment's protections for the right to free speech and voter suppression.
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