Found this in with a bunch of other Propaganda posters. It is a little different though, an artist picture of the end of the 1st World War (WW1). Two soldiers on a battlefield showing little emotion it has to be said. I guess this was used for years to come to celebrate the ending of the Great War, never forget.
This was a pretty standard poster for USA WW2. It was all about getting people to save, buy stamps, do their bit for the war effort. Using the stamps as ammunition going into the gun.