If there’s a silver lining for McDonald’s in Tuesday’s dreadful earnings report, it is that perhaps union activists will begin to understand that the fast-food chain cannot solve the problems of the Obama economy. The world’s largest restaurant company reported a 30% decline in quarterly profits on a 5% drop in revenues. Problems under the golden arches were global—sales were weak in China, Europe and the United States.

So even one of the world’s most ubiquitous consumer brands cannot print money at its pleasure. This may be...