Global Economy Slows, Pushing Europe’s Central Bank to Make a Surprise Move

FRANKFURT — Just a few months ago, the European Central Bank put the brakes on a vast economic stimulus program devised during the financial crisis. On Thursday, it unexpectedly reversed course and revived some of the measures, signaling the rising threat of a recession.

The quick turnabout, from confidence to concern, reflects the broader weakness in the global economy. A slowdown in China, exacerbated by rising trade tensions with the United States, has reverberated around the world, dragging down growth in Europe and elsewhere.