There were daily papers, pet dogs, a pistol on the cushion beside him. (6)
This is violence at the ready, domesticated. The gun is on par with the daily news and the pet dogs, all close and cozy with the colonel. The implication is that he might have a need to shoot at any time.
Broken bottles were embedded in the walls around the house to scoop the kneecaps from a man's legs or cut his hands to lace. (9)
What would Martha Stewart say about that? They're not exactly decorative. The fact is, there are angry or criminal people who want in. The people who are in want to keep them out. If it takes cutting kneecaps or shredding faces, well, so be it.
He spilled many human ears on the table. (21)
This warlord's bag of tricks is brimful of human ears. The flatness of the language and the ordinary gesture only serve to underline the horror at the violence that has occurred "offstage." You know that people had to be brutally killed, their ears cut from their heads, but you don't know for sure of the order of events. The violence of the poem centers on this image and what it says about this war, and about this despicable man.