Final answer:
Woodrow Wilson promised the American people that he would not send "your boys" to war, but he eventually had to send American troops to World War I.
Step-by-step explanation:
The president who promised the American people that he would not send "your boys" to war is Woodrow Wilson.
Woodrow Wilson took office in 1913 and believed in an idealistic foreign policy based on morality. He wanted to shrink the role of the United States in foreign affairs and intervene in international events only when there was a moral imperative to do so.
However, as tensions grew in Europe, particularly with Germany's morally reprehensible war tactics, Wilson eventually had to postpone American involvement in World War I. Despite his campaign promises, he could not completely avoid sending American troops to war.