Good for a short.
The drawings were good, but a background might have helped. The animation was incredibly smooth. And although the movement was fairly simple, it worked fine. The black lines in the background at the start didn't look exactly great as a couple of them just moved up and down.
The sound effects such as footsteps was in synch with the characters walking up and down, and the voices were also in time with the mouths moving. The voices also made the flash a bit funnier, although the solider was a little hard to hear.
For a flash about war there wasn't exactly a lot of violence. However, the character who went on a rant about war not being funny made some comments which could be cosidered violent, so it gave the rating higher than 0.
The play and replay button worked, but the replay button was a little hard to press since there wasn't a box around the text that could be pressed.
The angrieness of the guy was pretty funny. Beyond that there isn't really much to say. Other than the scribbled tree which was funny for some reason.
So to improve this just add a suitablly awesome background and make the replay button easier to hit.