On the other side of the Atlantic, cotton twill trousers made their appearance on the American continent during the Spanish-American War. The US Army already wore a khaki uniform, but this one was made of wool, so it was particularly warm. American soldiers stationed in the Philippines therefore quickly preferred to adopt cotton clothing and brought them back to the United States. This is why, at the beginning of the 20th century, American troops used straight trousers imported from China.
It was in 1902 that the Marines wore the Chino more officially, becoming the khaki uniform of American troops (during exercises and combat). It was all the more comfortable in the summer or in tropical climates. Over the decades, various corps of the American army will adopt the famous khaki. Starting with the airmen who will abandon their white clothes (often stained) to adopt in turn the khaki. In 1931, it was the turn of the navy submariners. It should be noted that during the Second World War, the entire American army (all branches combined) wore khaki as a summer service uniform in temperate climates.