The Roots of the Crisis

Via Delong, Jeffrey Sachs at Comment is Free:

Today's financial crisis has its immediate roots in 2001, amid the end of the Internet boom and the shock of the September 11 terrorist attacks. It was at that point that the Fed turned on the monetary spigots to try to combat an economic slowdown. The Fed pumped money into the US economy and slashed its main interest rate - the Federal Funds rate - from 3.5% in August 2001 to a mere 1% by mid-2003. The Fed held this rate too low for too long.

Monetary expansion generally makes it easier to borrow, and lowers the costs of doing so, throughout the economy. It also tends to weaken the currency and increase inflation. All of this began to happen in the US.

What was distinctive this time was that the new borrowing was concentrated in housing. It is generally true that lower interest rates spur home buying, but this time, as is now well known, commercial and investment banks created new financial mechanisms to expand housing credit to borrowers with little creditworthiness. The Fed declined to regulate these dubious practices. Virtually anyone could borrow to buy a house, with little or even no down payment, and with interest charges pushed years into the future.

As the home-lending boom took hold, it became self-reinforcing. Greater home buying pushed up housing prices, which made banks feel that it was safe to lend money to non-creditworthy borrowers. After all, if they defaulted on their loans, the banks would repossess the house at a higher value. Or so the theory went. Of course, it works only as long as housing prices rise. Once they peak and begin to decline, lending conditions tighten, and banks find themselves repossessing houses whose value does not cover the value of the debt.