Why did president wilson withdraw american troops from mexico in 1917?

The expedition began to approach its end when General Álvaro Obregón made a threat that if they did not stop, they would send troops from the Mexican army to cut supplies to US troops in Mexico. And after a confrontation between Mexican and American troops near the border, tension increased. Pershing, furious, requested to attack Chihuahua City, but due to the participation of the United States in the First World War, President Wilson did not accept.

In November 1916, the United States agreed to remove its troops from Mexico. But the American soldiers left Mexican territory until February 1917, and Pershing failed to capture Pancho Villa.

where is the passage

i cant solve it without knowing the passage

answer: both considered peasants valued members of society.

explanation: the ancient chinese and indian empires were large asian empires that had the same problems with other big empires, they had to work hard and sometimes fight in order to keep them united, they both relied heavily on their capacity to trade and to send strange and rare items to europe, and had the father as the head of the house hold in both societies, but they didn´t considered pleasants as valued members of their society, they were the bottom of the social pyramid in both of their societies.