He didn't fight for freedom, well he might have but most of his buds didn't.
People signed up before and during the war for many reasons, and more so they fought, stood their ground, advanced and died for many reason. Freedom isn't one of them.
Social pressure, joining with friends, boredom and adventure [yeah really], a place to be safe during the great depression [for those who were regular force], even King and Country, get in because they figure they would get drafted and wanted to pick their poison [and avoid being sent to the mud] but freedom. No. Loads of reasons, I've read more than a few accounts, freedom never comes up. And that covers who who signed up, never mind those who got in via selective slavery or whatever various countries called it back then.