In the end, the banking system was bolstered with the help of TARP and a separate Geithner initiative requiring the largest banks to undergo "stress tests." The tests calmed investors by showing that the banks could withstand an even worse downturn.
TARP distributed $245 billion to banks. So far, it's brought back $268 billion for a return of $23 billion.
Critics argue that under Geithner, the government failed to ensure that banks would use their TARP money to lend more to businesses and homeowners.
Geithner's approach won't prevent future crises, opponents further argue. They say big banks still feel free to make risky bets because of an implicit guarantee: that if their gambles fail, the government will save them, and the banks' executives won't be held accountable.
"Secretary Geithner protected the interest of the largest financial institutions, and we will pay a very heavy price for that," said Neil Barofsky, who was the government's top watchdog for TARP.Many private economists are less critical. They say Geithner achieved the fundamental goal of stabilizing the U.S. financial system without damaging the economy.
"The effort was a success and vitally necessary for ending the Great Recession and starting a recovery," said Mark Zandi, chief economist at Moody's Analytics.
Geithner and the administration endured intense criticism for giving bailout aid outside the banking system to American International Group.
The insurance giant represented everything the public detested about the government bailouts: Its rescue was the costliest at $182 billion. It spent $440,000 on spa treatments for executives only days after its rescue. It gave millions in bonuses to top executives, including those who'd made the risky bets that had unraveled AIG.
Geithner, who led the Federal Reserve Bank of New York before heading Treasury, was involved in the decision to save AIG in September 2008 and oversaw its bailout as Treasury secretary. Some of the rescue money went to fully repay banks that had invested in AIG. Critics called this a giveaway to banks that should have had to accept less than full payment.
Geithner and Federal Reserve Chairman Ben Bernanke have said that letting AIG fail would have threatened the entire U.S. financial system, in part because of AIG's outsize role in selling credit default swaps. These swaps were insurance-like guarantees on mortgage bonds. They required AIG to pay billions once the housing market went bust.
Supporters note that the government ended up profiting on its investment. AIG has repaid all the bailout money, and the government made $22.7 billion more than it provided.
Government bailouts of General Motors and Chrysler became a political issue in 2012. Republican Mitt Romney opposed rescuing the two companies. Obama countered that the bailout saved jobs at automakers, parts companies and other businesses. Both companies are now selling more cars, hiring workers and earning profits.
But unlike with the bank and AIG bailouts, the government is expected to lose money on the auto bailouts -- up to $24 billion out of the $80 billion it provided.