anti-war songs from WWI:

I Didn't Raise My Boy To Be A Soldier
Hanging on the Old Barbed Wire (anti-hierarchical, really)

Sister Susie's Sewing Shirts for Soldiers isn't exactly anti-war, but Susie, aside from being incompetent, may be stealing some flannel for her own use.

Lots of pro-war/pro-recruitment songs, which I won't list, and some songs that slip their pro-recruitment sentiments into the verse, like K-K-K-Katy:

Soon he'll go to France, the foe to meet.
Jimmy thought he'd like to take a chance, See if he could make the Kaiser dance,
Stepping to a tune, All about the silv'ry moon,
This is what they'll hear in far off France.

Interesting how so many pro-recruitment songs simplify the task to something like making the Kaiser dance. It reminds me of a time I was driving through the US near the beginning of the first Iraq war and people were phoning into the radio telling us it was time to "boot Sadam's ass."

I guess it sounds better than "come back home a broken man" which is what happened to my grandfather at the end of WWI. His lungs were damaged and the doctor told him he could no longer work his trade (horse-collar-maker) because of the dust and he became a tenant farmer--a very poor tenant farmer. We do have a very nice certificate, though, thanking him for his participation.