JPMorgan Chase CEO Jamie Dimon scrutinized the "demonization" of major financial institutions by politicians in his annual letter to shareholders. Mr. Dimon argued that large banks are needed for multinational companies to thrive. "We have to stop slipping into a cacophony of finger-pointing and blame," Mr. Dimon wrote. "While bad actors always should be punished, we also should note that not all who got into trouble were irresponsible." Mr. Dimon also wrote that he regrets issuing $40 billion in unsecured debt through a guarantee program of the Federal Deposit Insurance Corp.