The following is excerpted and adapted from Mr. Brooks' upcoming book "The Road to Freedom: How to Win the Fight for Free Enterprise," to be released on May, 8 2012.

Liberals often accuse conservatives of being obsessed by morality. But the truth is, many conservatives are reluctant to talk about morals or make a moral case for anything in politics and policy. They're willing to talk about principles, perhaps. Values, maybe. But morals? That evokes unpleasant memories of the "culture wars" of the 1990s, which focused on schismatic issues like abortion and homosexuality. As a result, many who strongly believe in free enterprise steer clear of all public "moral" arguments.

This is a mistake and a missed opportunity. A great deal of research shows that people from all walks of life demand a system that is morally legitimate, not just efficient. The moral legitimacy of free enterprise depends largely on how the system enables people to flourish, whether the system is fair, and how the system treats the least fortunate in society.

"The moral legitimacy of free enterprise depends largely on how the system enables people to flourish, whether the system is fair, and how the system treats the least fortunate in society." -- Arthur Brooks

Privately, free enterprise's champions talk about these things incessantly. While they generally believe in the need for a safety net, they celebrate capitalism because they believe that succeeding on merit, doing something meaningful, seeing the poor rise by their hard work and virtue, and having control over life are essential to happiness and fulfillment.

But in public debate, conservatives often fall back on capitalism's superiority to other systems just in terms of productivity and economic efficiency. What moves them is the story of their immigrant grandparents who came to America to be free; but what they talk about is the most efficacious way to achieve a balanced budget.

The dogged reliance on materialistic arguments is a gift to statists. It allows them to paint free enterprise advocates as selfish and motivated only by money. Those who would expand the government have successfully appropriated the language of morality for their own political ends; redistributionist policies, they have claimed to great effect, are fairer, kinder, and more virtuous. Too frequently, the rejoinder to these moral claims has been either dumbfounded silence or arguments about economic growth and corporate tax rates.

Average Americans are thus too often left with two lousy choices in the current policy debates: the moral Left versus the materialistic Right. The public hears a heartfelt redistributionist argument from the Left that leads to the type of failed public policies all around us today. But sometimes it feels as if the alternative comes from morally bereft conservatives who were raised by wolves and don't understand basic moral principles.

No wonder the general public is paralyzed into inaction, even when dissatisfaction with government is at an all-time high. There just doesn't seem to be a good alternative to the "statist quo," and as a consequence, the country is slipping toward a system that few people actually like. Most people, for instance, intuitively understand the urgent need for entitlement reform. But do you seriously expect grandma to sit idly by and let free-marketeers tinker with her Medicare coverage so her great grandkids can get a slightly better mortgage rate? Not a chance -- at least, not without a moral reason.

If conservatives want to win the fight for free enterprise, they are going to have to get comfortable making the moral case for it, right now.

Arthur C. Brooks is president of the American Enterprise Institute.