Luckily I didn't have to explain what the song meant. For those that don't know its based on the 1939 book "Billy Got His Gun" about a WWI soldier that awakens to find himself trapped in his own body after it is blown up and he looses his arms, legs and face and cannot see, hear or speak but his mind is left intact. He tries to communicate with his doctors about wanting to die first, then being toured around the country to show the horrors of war. In the end neither of his wishes are carried out and he is left to go mad in his own head flashing back to his past unable to determine reality (whats left of it) from insanity. Pretty disturbing and very anti-war, which is not surprising seeing how it was written at a time when the US was headed into yet another war in Europe and while there seemed to be no avoiding it, many felt the US should remain out of this one. Part of the reason the conspiracy theorists have maintained the government allowed the Japanese to bomb Pearl Harbor was as an excuse to get into the war; knowing that the military industrial complex would have the drive to dig the US economy out of the depression of the 30's.
I have seen some guys in the military use the song to "psych up" with the headbanging riffs and very misunderstood military theme of the song...still, it ranks up there as a metal classic in all regards.