"I wear the black for the poor and beaten down
Livin' on the hopeless, hungry side of town
I wear it for the prisoner who has long paid for his crime
But is there because he's a victim of the times..."
"I wear it for the sick and lonely old,
For the reckless ones whose bad trip left them cold
I wear the black in mourning for the lives that could have been
Each week we lose a hundred fine young men..."
-"Man in Black"
Doesn't sound like something a conservative would sing about.
Maybe your view of "conservative" isn't accurate. I'd say those are things most people agree with regardless of political ideology.
Wars have been started and supported by both parties for generations. The left has done a great job of brainwashing people of believe they're the party of the middle class, the working man, but they've done nothing to help them. Baltimore, Chicago, New York, etc...
That's why you assume those lyrics are anti-conservative and pro-left.