The nation's six largest banks reported $23 billion in profits in the second quarter, but they could end up victims of their own success.
In recent weeks, the Treasury Department, senior regulators and members of Congress have stepped up efforts intended to make the largest banks safer. The banks have warned that more regulation could undermine their ability to compete and curtail the amount of money they have to lend, but the strong earnings that came out over the last week could undercut their argument.
The most pressing concern for banks is a relatively tough new rule that regulators proposed last week that could force banks to build up more capital, the financial buffer they maintain to absorb losses. But the banks did not demonstrate any difficulty in meeting the proposed rules, and the banks now appear to have fewer allies in Washington than at any time since the financial crisis.
This was highlighted on Wednesday when the Treasury secretary, Jacob J. Lew, effectively issued an ultimatum to Wall Street, calling for the swift adoption of rules introduced through the Dodd-Frank financial overhaul law, which Congress passed in 2010. Mr. Lew also said that he might be open to stricter measures if enough had not been done to remove the threat that big banks can pose to the wider economy.
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