Why did US had fewer casualties then many other countries in the world war l?

The United States had fewer casualties in World War I compared to many other countries primarily because it entered the war later, in 1917, after the initial major battles had already taken place. Additionally, the U.S. military was not as heavily engaged in the prolonged trench warfare that characterized much of the conflict. While American forces played a crucial role in the final offensives, their involvement was shorter and more concentrated, contributing to relatively lower casualty rates.