Loosening The Ties That Bind

Maybe if economics were a pure science, its dictates would be immutable. But when mixed up in the messy art of politics, it has a vexing tendency to go sloppy. Last week brought a telling example of how one unprecedented experiment in budgetary governance — the euro zone's Stability and Growth Pact — went awry, leaving governments and economists bickering over their numbers and Brussels, as usual, in the doghouse.

Like many imperfect ideas, the Stability Pact seemed golden when it was created. In 1997 the only cloud on the horizon of monetary union was inflation. There had...