Over at my old Time.com stomping grounds, Adam Cohen has written a fascinating article about the movement to have the federal minimum wage declared unconstitutional. This goes hand-in-hand with the emergence of the minimum wage as a campaign issue in the midterm elections. My question: Why do people care so much?

For much of its recent history, the federal minimum wage hasn't even been all that binding. State minimum-wage laws have led to higher pay, or companies paid more on their own. According to the Labor Department, only 980,000 people made the federal minimum wage last year. Even when you add in the 2.6 million workers who made less (people like tip-collecting waitresses and teenagers just working for the summer), you still only wind up with 4.9 percent of all hourly-paid employees-- and just 2.9% of the total U.S. wage-earning workforce.

Yes, it's true, in Econ 101 we all learn that price floors disrupt the most efficient allocation of resources in a marketplace. When it comes to low-wage workers, that leads to companies hiring fewer people than they would otherwise, leaving some folks who want jobs without them.

But those who make it beyond one semester of economics find out that the world doesn't always work the way a rudimentary model would predict. In fact, in recent years economists have struggled to find explanations for real-world situations in which higher wages do not, in fact, lead to lower employment. One theory: a higher wage forces employers to invest in their employees and figure out ways to make them more efficient (i.e., valuable). As Richard Florida likes to argue, boosting efficiency in low-wage (mostly service sector) jobs is exactly what we should be doing right now.

But I digress. Back to my original question: Why do people care so much about an economic policy that doesn't seem to have much of an impact on the economy? One reason might be because of the anchoring effect of the minimum wage. Even if only a few people are earning the minimum wage, its existence still sends a signal to the market that this is about what it should cost to hire an unskilled worker. That tinkers with the expectations of both companies and workers. Or, what I might be quicker to believe: talking about the minimum wage—whether you want to increase it or abolish it—is a proxy for saying "I care about struggling workers," or "I don't want government telling business what to do."

The problem with using the minimum wage to have this debate, though, is that no matter who wins, the victory will be hollow. If we want to help low-income families, we could do a lot more than change a wage many of them don't make anyway. And if we want to minimize government intervention in free enterprise, we might choose a battle that is meaningful to companies outside of such a narrow range—half of all minimum-wage workers have jobs in the leisure and hospitality industries.

Although maybe saying that just goes to show how naive I am about politics. Maybe in that realm the best battles to fight are the ones that are the least likely to change the status quo no matter what the outcome is.