How did Andrew Johnson help with manifest destiny before he was even Vice President?

Before becoming Vice President, Andrew Johnson supported the concept of Manifest Destiny through his advocacy for westward expansion and his belief in the United States' divine mission to spread democracy. As a congressman and later as the governor of Tennessee, he promoted policies that facilitated the settlement of western territories. Johnson also endorsed the annexation of Texas and the acquisition of other lands, which aligned with the Manifest Destiny ideology, emphasizing the nation's growth and the expansion of its borders.