"We met as soul mates"
The soldiers were enthusiastic, buddies, and hopeful for a better life.
"We left as inmates, from an asylum"
The soldiers dreams/ideas of heroism, and valour were completely wrong
"And we were so gung ho to lay down our lives"
The soldiers thought they'd be heroes, that when they came back, they would be revered as fighters for freedom.
"And WE were sharp; as sharp as knives"
"And THEY were sharp; As sharp as knives"
Equalizes America and Vietnam. Both were as deadly as each other.
"They sent us Playboy; They gave us Bob Hope"
Weak, useless, temporary distractions. Just like drugs. A temporary "getaway" from the reality of war, guts, and blood.
"We dug in deep, And shot on sight, And prayed to Jesus Christ with all of our might"
These two lines just accentuate the fear that resided in the lives of the soldiers.
(Relates to Platoon). As in Platoon, where the imagery is dark and colours are dull, the soldiers couldn't see anything and shot anything that moved. To the soldiers, who or why didn't matter at that time, it was their life or the shoot.
Their country forsook the soldiers. Their countries had sentenced them to near certain death in Vietnam in a hopeless situation. Their country left them to die there. The American people hated the soldiers, they spat on them. To them, their home countries had betrayed them. In this case, all that seemed to be left was God.
"And it was dark, so dark at night"
This has two meanings: the literal and metaphorical. In the literal sense, the atmosphere was dark for the soldier (Relates to Platoon). The soldier was disillusioned, and couldn't see anything. Just as in Platoon.
In the metaphorical sense, darkness stands for...