Final answer:
World War I was waged to make the world safe for democracy.
Step-by-step explanation:
The war that was waged "to make the world safe for democracy" was World War I. This phrase was coined by President Woodrow Wilson as a justification for the United States' entry into the war. Wilson believed that by joining the war, the US could help establish and protect democratic principles around the world. However, it is important to note that this argument was met with debate and criticism both at the time and in subsequent years.
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