[221]
Jefferson's popularity further suffered in his second term due to his response to wars in Europe. Positive relations with Great Britain had diminished, due partly to the antipathy between Jefferson and British diplomat Anthony Merry. After Napoleon's decisive victory at the Battle of Austerlitz in 1805, Napoleon became more aggressive in his negotiations over trading rights, which American efforts failed to counter. Jefferson then led the enactment of the Embargo Act of 1807, directed at both France and Great Britain. This triggered economic chaos in the U.S. and was strongly criticized at the time, resulting in Jefferson having to abandon the policy a year later.[222]
During the revolutionary era, the states abolished the international slave trade, but South Carolina reopened it. In his annual message of December 1806, Jefferson denounced the "violations of human rights" attending the international slave trade, calling on the newly elected Congress to criminalize it immediately. In 1807, Congress passed the Act Prohibiting Importation of Slaves, which Jefferson signed.[223][224] The act established severe punishment against the international slave trade, although it did not address the issue domestically.