Ask someone to describe what sets America apart from the rest of the world and the word “equality” almost surely will come up.

But what exactly do we mean by that term?

Do we mean everyone is equal in terms of their material possessions? Obviously not. Yet, when we hear politicians stoke the fires of class warfare and fan the flames of envy, it’s apparent that all too many people believe that a “level playing field” means we’re all more or less the same in terms of what we own.

Look again at the Declaration of Independence. Our inalienable rights include “Life, Liberty, and the pursuit of Happiness.” Note the phrase “the pursuit of.” However much certain politicians may want insist otherwise, no one is guaranteed happiness — only the right to strive for it.

How far you go is up to you. You don’t have to be born in a special class to succeed. That fact is crucial to understanding what truly sets America apart.

Take the Rev. Rick Warren, whom I recently ran into at Washington Dulles International Airport. An internationally known author and pastor, he was named by Time magazine in 2005 as one of the “100 most influential people in the world.” But it took a lot of hard work for this son of a Baptist minister and a high-school librarian to get there.

In 1980, Mr. Warren’s Saddleback Church in Orange County, Calif., held its first services with about 200 people in attendance. Today, Saddleback boasts an average weekly attendance of 20,000, and is the eighth-largest church in the country.

No one guaranteed Mr. Warren’s success. He went out and made it happen himself. America gave him the same freedom to succeed that it gives everyone.

It’s all too easy to take this for granted, but we shouldn’t. As bestselling author and pundit Dinesh D’Souza told a Heritage Foundation audience in 2006: “If I had remained in India, I would probably have lived most of my life within a five-mile radius of where I was born. I would undoubtedly have married a woman of my identical religious, socioeconomic and cultural background. I would almost certainly have become a medical doctor, an engineer or a software programmer. In sum, my destiny would, to a large degree, have been given to me.”

Mr. D’Souza didn’t want to be a doctor, an engineer or a programmer. He wanted to be a writer. In America, he could pursue that dream — and go as far as his talent and determination could take him.

This opportunity we enjoy as Americans flows in large measure from our capitalist system. That system enables anyone to start with a little and build it into something substantial over the course of a working lifetime.

America has more millionaires and billionaires than all the other countries in the world. Fully 80 percent of wealthy Americans started at the bottom and earned their money in one generation as the result of starting and building capitalistic enterprises. Look at Robert Goizueta, a refugee from communist Cuba who went on to become the CEO of Coca-Cola Co., and countless other examples.

To prosper as a socialist, you need to threaten the people. But to prosper as a capitalist, you need to please the people. Who can succeed as a capitalist? Who can achieve the American Dream? In America, the answer is anyone willing to work hard for it. That’s your only guarantee, in fact — a shot at success, not success itself. That’s up to you.

“In America,” Mr. D’Souza adds, “Your destiny is not prescribed; it is constructed. Your life is like a blank sheet of paper, and you are the artist.” Don’t believe those who insist that the picture is beyond your control. Unless you surrender it, the brush is in your hand.

Ed Feulner, president of the Heritage Foundation (heritage.org), is co-author of “The American Spirit: Celebrating the Virtues and Values That Make Us Great” (Thomas Nelson, 2012).