Biden just made one of the best decisions of his presidency

On Monday morning, President Joe Biden made the most important hiring decision of his first term, at least so far as the economy is concerned: He announced he would be reappointing Jerome “Jay” Powell as chair of the Federal Reserve. Lael Brainard, a fellow Fed board member widely rumored to be the runner-up for Powell’s job, would be tapped as vice chair.

The Fed is perhaps the most underappreciated policymaking body in Washington. It sets what’s known as the federal funds rate, which determines the cost of borrowing for banks and, in...