Federal Reserve Chairman Ben Bernanke has a piece in today's Washington Post. He explains what they're doing with QE2. He defends the Fed against charges that quantitative easing will stoke hyperinflation. And he says that Congress and the White House are part of the solution, but he doesn't state what their roles might be.

Although asset purchases are relatively unfamiliar as a tool of monetary policy, some concerns about this approach are overstated. Critics have, for example, worried that it will lead to excessive increases in the money supply and ultimately to significant increases in inflation.

Our earlier use of this policy approach had little effect on the amount of currency in circulation or on other broad measures of the money supply, such as bank deposits. Nor did it result in higher inflation. We have made all necessary preparations, and we are confident that we have the tools to unwind these policies at the appropriate time. The Fed is committed to both parts of its dual mandate and will take all measures necessary to keep inflation low and stable.

The Federal Reserve cannot solve all the economy's problems on its own. That will take time and the combined efforts of many parties, including the central bank, Congress, the administration, regulators and the private sector. But the Federal Reserve has a particular obligation to help promote increased employment and sustain price stability. Steps taken this week should help us fulfill that obligation.