Capote Justifying the acts of Perry and Dick?

While reading in this section, at times I felt as though Capote was indeed trying to make Perry and Dick look like cold-hearted killer for murdering the Clutter family. But I also noticed that in some lines he seemed to almost be trying to explain their actions. Attempting to present a reasonable argument as to why Perry and Dick could and felt the need to go through with what they did. On page 43-44 Capote writes: “All right, you think they’re fools, you despise them because their morals, their happiness is the source of your frustration and resentment. But these are dreadful enemies you carry within yourself. In time, destructive as bullets. Mercifully, a bullet kills its victim. This other bacteria, permitted to age, does not kill a man but leaves in its wake the hulk of a creature torn and twisted; there is still fire within his being but it is kept alive by casting upon it faggots of scorn and hate.” I interpreted this passage as Capote’s way of attempting to justify the thoughts of Perry, leaving room for his reader to interpret things in to different ways. Any thoughts?