There are certainly two forms of propaganda. The contrast is quite impressive as shown by these two songs in the following clips from from two different 1968 movies, the Green Berets and Oh what a Lovely war.

http://www.youtube.com/watch?v=pPgf32kwIE8

http://www.youtube.com/watch?v=5f95idVQEXI

Here are a few more catchy tunes;

They were only playing leap frog

and the unforgettable

The Bells of Hell go ting a ling a ling

Letting the children know about the history of conflicts shouldn't be confined to leaving out the warts as done so consummately by the Hollywood film machine. (which is where I suspect most youngsters get there information about historic events)

If children want to know about WW2 etc, etc then the best place to start is with the 1960s ITV series ' The World at War' - not the Warcraft Computer game.