Paulson had some sort of intuitive moral sense that it was time for some bank to pay for its mistakes.

David Brooks writes in The New York Times:

In theory, Ben Bernanke, Henry Paulson and Tim Geithner were as well prepared as anyone for this sort of event. Bernanke had spent his life studying the Great Depression; Paulson had led the world’s most prestigious investment bank; Geithner had been involved in financial rescues in Asia and beyond.

Moreover, all of them were expecting some kind of crisis. They knew there had been a dangerous surge of debt.

And yet as the panic unfolded in 2007 and 2008, they continually underestimated its scope and implications. In July 2007, Bernanke estimated global losses from the subprime mortgages and other loans of $50 billion to $100 billion. The losses turned out to be in the neighborhood of $4 trillion. In October of 2007, Bernanke said the banking system was healthy and doubted that the housing woes would destabilize it. He was wrong.

Their decision not to bail out Lehman Brothers was based on a complete misreading of the economic psychology. Paulson was sick of doing bailouts. He seems to have had some sort of intuitive moral sense that it was time for some bank to pay for its mistakes. Bernanke and Geithner went along, and none of them anticipated the meltdown that followed.