Why won't the Fed raise interest rates?

The U.S. Federal Reserve pulled out all the stops for the Great Recession. But when the next recession comes, the Fed’s toolkit is looking rusty.

“If there were to be a negative shock to the economy…we don’t have a lot of room using our traditional tried and true methods to respond,” Fed Chair Janet Yellen told Congress Tuesday during her semiannual testimony on the U.S. economy.