The History of the US Army on the Mexican border

On April 5, 2018 President Trump signed a Memorandum announcing his intention to deploy National Guard to the southern border. Shortly thereafter, all four border states either deployed or increased National Guard levels to their border with Mexico to assist Border Patrol. Other states such as Missouri, South Carolina and Mississippi have sent small teams of National Guard. While the political pundits, editorial boards and all around know-it-all types hoot and holler on radio and tv whether this is needed or legal, we felt it appropriate to show you the history of our military's involvement in border operations since before Texas became a country. 

This paper below is an outstanding history of the US Army, and in the late 20th century other branches of the military, operations at the US/Mex border since Texas Independence. As early as the mid 1990s, US Army and Marine patrols have conducted scout and surveillance missions involving both regular and Special Forces units on the border. On occasion they have traded fire with drug traffickers also. This was made possible with exemptions from Posse Comitatus rules though at no time were the military to enforce law against US citizens. Though a long read it is well worth the time in helping the reader to understand why President Trump is well within his rights to bring in the US military to the border. There has been over 200 years of precedence for the military to lawfully conduct operations. One common denominator is the failure of the US Army and starting in 1924, the US Border Patrol, to effectively control the border and prevent cross border raids, drug smuggling and illegal immigration. Though these failures are due to policy in Washington and not because of either Dept of Defense or US Border Patrol policies.