Answer:
President Woodrow Wilson sent troops into Mexico in 1916 to search for Pancho Villa, who had attacked Columbus, New Mexico. It was called the Pancho Villa Expedition.
Explanation:
The Pancho Villa Expedition was a military action by the United States against the Mexican revolutionary Pancho Villa in 1916 and 1917.
The expedition was a response to Villa's attack on Columbus in March 1916, in which several dozen Americans were killed. The American president Woodrow Wilson ordered General John J. Pershing with 10,000 men and a few planes to look for Pancho Villa to arrest him. The Americans received permission for this from the Mexican president Venustiano Carranza. An additional reason for the US military was to gain experience with a view to the First World War.
The expedition was not a success, and even proved counterproductive. The ongoing American involvement with Mexico (the American ambassador had been involved in the coup d'etat against Francisco I. Madero in 1914 and American troops had occupied the port city of Veracruz for a while) further fueled anti-American sentiments. Villa proved to be exceptionally agile when it came to hiding, experience he had gained during his previous career as a bandit. Reportedly, Villa even managed to hide in a horse's skin to escape from the Americans. On June 21 a battle was even delivered between American troops and the regular Mexican army in the battle of Carrizal, after which a war between the United States and Mexico could hardly be prevented.
Although some of Villa's officers were eliminated, the intervention was unsuccessful. The search was canceled on February 7, 1917.
