The 16th amendment (graduated income tax) and 17th amendment (direct election of senators) were originally ideas of POPULIST PARTY (an 1890s successful 3rd party who never won a presidential election)
This is evident in the fact that though the Populist Party never won a Presidential election, they were more successful in influencing the political landscape of the United States during their existence.
Some of the tensions that resulted in South Carolina’s rejection of federal authority during president Jackson’s administration include the readiness of President Jackson to use federal force in order to preserve the Union. Jackson also differed with his vice president Calhoun over the nullification issue which led Calhoun to resign