У них просто не было другого выхода кроме как прикончить Lehman

[vit_r]

Given the potential chaos that would have resulted from Bear Stearns filing for bankruptcy, the Fed had little choice but to engineer a rescue. In doing so, the Fed argued that the rescue was a rare, perhaps once-in-a-generation, event.
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When Bear was rescued, the Fed created a new lending facility to help provide bridge financing to other investment banks.
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Against this backdrop, if the government had rescued Lehman, it would have repudiated the claim that the Bear rescue was extraordinary; it would have also conceded that in the six months since Bear failed, neither the new facility that it set up nor the other steps to make markets more robust were reliable. Essentially, the Fed and the Treasury would have been admitting that they had lied or were incompetent in stabilizing the financial system — or both.

The F.A.Q.’s of Lehman and A.I.G.
By Douglas W. Diamond and Anil K. Kashyap