Joel Kotkin and Virginia Postrel do some good work trying to make income inequality a topic that conservatives are allowed to be interested in. It’s an excellent start.

There are plenty of good reasons for conservatives–and all Americans–to hope that Mitt Romney is elected president. But there are also a few factors that should give conservatives, in particular, some concern. At the most superficial level, there’s the precedent in electing the wealthiest man to ever hold the office. There’s no reason to fixate on this fact, but neither should its possible consequences be brushed aside.

Then there’s the question of what the defense of that wealth might cost. For instance, it should not force conservatives into defending the idea that the pursuit of wealth is the paramount American ideal. Nor should it force conservatives to defend all forms of wealth generation as noble, valuable, and good.

This last bit is already something of a problem for many conservatives. We tend to react to the left’s general distrust of the free market by insisting that every market-based outcome is efficient, helpful, and wise. We tend to react to the left’s general demonization of wealth by insisting that every rich guy deserves his fortune and that all transfers of wealth within the marketplace are inherently admirable and optimal.

But we ought to understand that very few markets are actually free, that even free markets frequently produce failures, and that some forms of wealth generation may be–while perfectly legitimate–more about gaming the financial system than creating any intrinsic value.

Jacob Weisberg’s analysis of why private equity is problematic for Romney, for instance, ought to trouble conservatives. Some samples:

It’s not clear that private equity—like other forms of financial innovation—is good for America. You’d think that if private equity made businesses more efficient and valuable overall, there’d be clear evidence to support it, but there isn’t. Private equity firms earn most of their money through financial engineering. A big share of their returns comes from “tax arbitrage”—figuring out how to exploit loopholes to pay less to the government. Because interest is a deductible business expense, debt financing means they often pay little or no corporate tax. Private equity’s reliance on leverage can also magnify short-term earnings without leaving the companies they manage more valuable overall. One legal but dubious practice that private equity firms engage in is paying large “special dividends” out of borrowed money.  As Jim Surowiecki of the New Yorker has written, “These dividends created no economic value—they just redistributed money from the company to the private-equity investors.” There’s some anecdotal evidence that the well-regarded Bain has been a better owner than most. But there’s no real way to evaluate that either.

And then there’s this:

It’s telling that George Romney, Mitt’s father, made around $200,000 through most of the years he ran American Motors Corporation. Doing work that clearly created jobs, the elder Romney paid an effective tax rate that averaged 37 percent. His son made vastly more running a corporate chop shop in an industry that does not appear to create jobs overall. In 2010, Mitt Romney paid an effective tax rate of 13.9 percent on $21.7 million in investment income—around 14 times as much as his father in inflation-adjusted terms. This difference encapsulates the change from corporate titans who lived in the same world as the people who worked for them, in an America with real social mobility, to a financial overclass that makes its own separate rules and has choked off social mobility. The elder Romney wasn’t embarrassed to explain what he’d done as a businessman or to release his tax returns.

This isn’t to say that private equity is scandalous or that Mitt Romney is a rascal. It’s merely to point out that if conservatives wish to support Mitt Romney (and they probably should), it’s not necessary that they be stampeded into defending the entire “private equity” view of the world.