Mitt Romney boasts about it. So do Herman Cain, Gary Johnson, and Michele Bachmann.

But is the private-sector experience that these presidential-nomination hopefuls possess an ipso facto asset for elected office? Do the skills of a successful businessperson automatically mirror those of a successful president? Is running a company akin to leading a country?

All four candidates are hoping voters will answer affirmatively. Cain’s entire campaign, in fact, is predicated on the notion that his background as a businessman (he has never held public office, but asserts ad nauseam that he’s a “problem-solver”) adequately prepares him for the White House. The remaining three also crow about their private-sector experience, but they’ve all held (or hold, in the case of Bachmann) political office. Cain necessarily puts it front and center.

Luckily, it seems many Americans are skeptical about the inherent value of business experience for political candidates.

In a recent Pew Research poll, 49 percent of respondents said it wouldn’t matter if a given candidate had been a business executive — it wouldn’t influence their level of support. Thirty-five percent of those polled said they’d be more likely to back a candidate with business-executive experience; 14 percent said it would make them less likely.

(The same poll found that just 9 percent of those polled said they’d be more likely to support a candidate who has never held elected office.)

Certain skills — oratory, leadership, etc. — are undoubtedly useful in both the White House and the boardroom, and private-sector experience can be an asset. But it’s an asset *only* insofar as it gives elected officials firsthand knowledge of how small businesses or corporations work — not as a model for governance.

I’m a leftist but no strident anti-capitalist; the market has its place. (Markets are clearly the best vehicle for wealth creation. How said wealth is distributed or if worker agency exists are of course different questions.) And as others have perceptively argued, you can improve the delivery of government services without adopting the market paradigm wholesale.

On the whole, though, public and private should not be conceptually confused. The private sphere is often about profit, economic efficiency, and individual gain. The public sphere should be about equity, self-governance, and collective goods. Transposing market values on the public sphere would be a perversion of our democracy.

Johnson, however, has pledged to do just that.

His website states that the former New Mexico governor “brings a distinctly business-like mentality to governing, believing that decisions should be made based on cost-benefit analysis rather than strict ideology.”

Much as Johnson might wish to frame decision-making as superseding “strict ideology,” his (and everyone else’s) policy prescriptions are ineluctably colored by his political persuasions. (It’s worth noting that I do support a good deal of what Johnson has to say, especially when it comes to foreign policy.)

For example: Even if many agree we should address the deficit, solutions vary wildly.

After a cost-benefit analysis, some would conclude that Paul Ryan’s plan is the most effective way to bring down the deficit and reform entitlements. In contrast, I regard the Ryan plan as an abomination, because it would hurt some of the most vulnerable in society and wouldn’t pare back military spending.

So why the differing opinions, even when the same evaluative method is being employed? Because cost-benefit analyses in public policy involve more than just dollars and cents; analyzing potential remedies may begin with a “cost-benefit analysis,” but opinions on a given policy are influenced by values and, yes, ideology.

In business, everything comes down to what hinders and what spurs the making of profits. But in the more participatory public sphere, citizens have different conceptions of the good life, what services the government should provide, and what type of image America should project to the world.

Sorting out these and other differences is the stuff of democratic politics.

In short, I want a president who understands the market. But I also want a president who knows the difference between the public and private sector. Many GOP presidential-nomination contenders seem to be conflating the two.