What was John Quincy Adams worst mistakes?

John Quincy Adams' worst mistakes include his inability to effectively navigate the political landscape post-presidency, particularly in failing to build a strong coalition to support his policies. His controversial "Tariff of Abominations" in 1828 alienated many Southern voters, contributing to his loss in the 1828 election. Additionally, his stance on slavery, particularly his initial hesitance to confront the issue directly, and later his role in the Amistad case, revealed a complex and often contradictory approach that frustrated both abolitionists and pro-slavery advocates.