The terrorist attacks on 11 September 2001 forever changed the way in which the United States of America approached the question of border security. President George W. Bush almost immediately reiterated a historically famous political reaction to secure the United States border with Mexico, believing the southwest border to be an easy entry point for radical terrorists looking to do harm upon the United States. Presidents Woodrow Wilson, Ronald Reagan, and Bill Clinton, after they took office, also faced menacing border security challenges, and focused hard on securing the border with Mexico. The contention was that United States national security was in jeopardy and that cross-border military force was an option to restore order along the Rio Grande. President Ulysses S. Grant used the same justification to defend the bloody attack on the Mexican Kickapoo Indians in May 1873, by the Fourth Cavalry, under the command of Colonel Ranald S. Mackenzie. This raid has many lessons applicable to contemporary borders security operations.