Jimmi never wrote any war songs, dunno about Elvis. But really, a war song by Elvis, probably a good thing I don't know about it.
Funny thing about Hendrix, somehow he retains a left wing image, Purple Haze is supposed to be about Vietnam, it ain't, Hendrix himself made it clear several times in interviews that he wanted communism to be fought actively.
Hej Dude is supposed to be an anti-gun anthem, it ain't, it's a blues song with a very common blues theme, 'ohh woe is Joe, he shot his girlfriend'. It's very Woody Leadbelly and not political at all.