The "blue" has already gone to **** and Walt doesn't give a damn. And the DEA isn't going to let Jesse cook. So while Walt's empire was his pride and joy at one point, I don't see that being the target to "hit him where it hurts most" now. Also, Walt already surrendered his pride over being "Heisenberg" with the confession that Hank was the man. He knows Jesse knows the truth, Hank knows the truth, and the Lydia and Co know the truth - so I don't see the motivation in protecting an empire he already let go of. Walt's entered his "end game" phase where simply staying out of jail, keeping Walt Jr unaware, and keeping his money are his priorities. I don't think the empire or Heisenberg really means as much to him now. That said, I won't rule out them going there with the story, although it will take some solid writing to make that leap believable to me now (which they've proven plenty capable of). Maybe it's a different shot at his pride, not just the Heisenberg aspect.
I still think it comes back to Walt's family (including his supporting of them - the cash) in some way. Jesse and the DEA won't intentionally put them in danger, but maybe it works out that way indadvertently.
They also keep making it clear that getting Walt is first priority for Hank, so I do think he plays some role in the family being harmed/killed - whether it's putting them in harm's way, not protecting them when he should have known beter, etc.
[This message has been edited by DannyDuberstein (edited 9/4/2013 3:13p).]