Jimi Hendrix - Machine Gun
Jimi Hendrix's version of All Along the Watchtower - about impending conflict

Yeah Goodnight Saigon..forgot about that one...what an amazing song

Iron Maiden has two of the best "war" themed songs EVER....

"Paschendale"
"The Longest Day"

Check 'em out - you'll be very impressed. (Pay close attention to the lyrics as well...)

Television - "Foxhole"
The Jam - "Little Boy Soldiers"

And one of my all-time favorites, The Kinks' "Some Mother's Son", which I think is an emotionally wrenching tune.

War is Stupid by Cluture Club (1985)

I would second Iced Earth's "Glorious Burden"

And I'd check out more Maiden "Trooper" and "Aces High"

I love Pearl Jam's "Army Reserve" - although it's from the perspective of the family left at home.

System Of A Down : BYOB
Iron Maiden : 2 Minutes To Midnight

Zombie Cranberries

"Viet Nam" by Jimmy Cliff
"Shipbuilding" by Elvis Costello

and on a ligher note:

"G. I. Jive" by Louis Jordan