Walter's done a lot in his life that is at best questionable. Lately, I've been wondering to what degree he regrets any of it. In the season 1 ep, The Arrival, Walter drugs astrid. And while he seems to feel bad about it, he doesn't apologize. I can't remember Walter ever apologizing for anythng he's done, at least not the big stuff. He hasn't apologized for the Cortexiphan trials or kidnapping Peter. He simply tries to justify what he did, even if it is ultimatley unjustifiable. Does Walter regret anything he's done, or does he simply feel bad about the consequences without actually regretting the action? And what does this say about him?