 Scott drew up an invasion plan that would begin with a naval assault on the Gulf port of Veracruz and end with the capture of Mexico City.With Congress unwilling to establish the rank of lieutenant general for Democratic Senator Thomas Hart Benton, Polk reluctantly turned to Scott to command the invasion.Among those who joined the campaign were several officers who would later distinguish themselves in the American Civil War, including Major Joseph E. Johnston, Captain Robert E. Lee, and Lieutenants Ulysses S. Grant, George B. McClellan, George G. Meade, and P. G. T. Beauregard.