I find that this episode marks the transition for Tony the "character," from someone who is redeemable to straight sociopath. I have long believed that the Tony from season one was originally created as someone who still had a strict moral code, and who could still maybe escape this with his soul intact. David Chase changed his mind and wanted Tony to be a terrible and immoral person. Hence the Tony from season 3 on seems to only be capable of destroying things and people.

"strange things happen all the time, and so it goes and so it goes. and the book says, 'we may be through with the past, but the past is not through with us'" - MAGNOLIA