Why’d the Fed rescue Bear? Felix Salmon has the answers:

Simple: Counterparty risk. Bear Stearns is a major broker-dealer; billions of dollars of obligations flow through it every day. If suddenly that flow was halted, and Bear defaulted on its obligations, there would be a huge risk to the entire financial system. As Herb Greenberg puts it, “if the hedge funds and rich folk get caught here, without a net, you imagine possible domino effect throughout the brokerage and banking industries as people start pulling out cash and heading for safer pastures, such as trust companies.” And the Fed simply can’t risk the entire banking industry imploding like that.

From the whole article, it sounds like Bear is cooked no matter what. The intervention is just to prevent creditors from being brutally de-pantsed. Stockholders are getting savaged.