To avoid large and unsustainable budget deficits, the nation will ultimately have to choose among higher taxes, modifications to entitlement programs… - Ben Bernanke

House prices have risen by nearly 25 percent over the past two years. Although speculative activity has increased in some areas, at a national level these price increases largely reflect strong economic fundamentals, including robust growth in jobs and incomes, low mortgage rates, steady rates of household formation, and factors that limit the expansion of housing supply in some areas.

I want to make sure you keep your eyes on the ball, that is, the two basic missions of a central bank. The first is maintaining macroeconomic stability: maintaining stable growth and keeping inflation low and stable. The principal policy tool for maintaining macroeconomic stability is monetary policy. In normal times, the Fed and other central banks use open market operations—purchases and sales of securities in markets—to move interest rates up or down, and in doing so try to create a more stable macroeconomic environment.
The second part of a central bank's mission is maintaining financial stability. Central banks are focused on trying to ensure that the financial system functions properly, and in particular, they want to prevent, if possible, and if not, to mitigate the effects of a financial crisis or a financial panic.

There’s no denying that a collapse in stock prices today would pose serious macroeconomic challenges for the United States. Consumer spending would slow, and the U.S. economy would become less of a magnet for foreign investors. Economic growth, which in any case has recently been at unsustainable levels, would decline somewhat. History proves, however, that a smart central bank can protect the economy and the financial sector from the nastier side effects of a stock market collapse.