The trenches are actually those in "All quiet on the Western Front"

Soldiers die for the powerful - while being deluded into it being something honourable. 

In the hours after the end of WW1 had been agreed upon,  thousands more died just because the commanders wanted to set a time as official end that felt meaningful  (11 November 11:00) - so they didn't immediately transmit the end to the front lines. 

Ain't that cynical. 

If you want a real anti-war movie, go watch that one or Grave of the Fireflies.