Less than two months after being chosen to lead the International Monetary Fund, Christine Lagarde shook up last weekend’s conference of central bankers in Jackson Hole, Wyo., with an urgent, much needed plea for bolder economic policies in the United States and Europe to head off a looming double-dip recession.

When Ms. Lagarde, then France’s finance minister, was campaigning to become the fund’s managing director, it was uncertain whether she could look beyond the politicians’ obsession with austerity that has repeatedly defeated efforts to contain Europe’s worsening debt crisis and continues to stymie effective policy making on both sides of the Atlantic.

Now free to speak her mind, her blunt remarks and prescriptions were just what the central bankers needed to hear. She rightly called for: rebalancing global trade by stimulating demand in developing countries with big export surpluses; more aggressive mortgage relief in the United States; and giving job creation priority over deficit reduction in the United States and Europe.

She also called for substantial injections of public and private capital into dangerously frail European banks. And while citing the necessity for long-term deficit reduction, she made clear that near-term policies must give priority to generating jobs, stimulating demand and renewing economic growth.