Where, oh where, will mainstream retailers find growth in a stagnant economy with debt-besotted consumers?

Obviously, not in America.

Behemoth U.S. retailers such as Wal-Mart (NYSE: WMT), Best Buy (NYSE: BBY), and Costco (Nasdaq: COST) are increasingly looking at opportunities on foreign shores, because other nations offer much greater potential for revenue growth than ours.

According to Reuters, Wal-Mart has been focusing on international operations:

Growth outside the United States has been key for the world's largest retailer, as its core U.S. customer has been hit by high unemployment and recently rising gasoline prices.

Walmart's international sales rose about 11 percent last year -- eclipsing $100 billion for the first time. International accounts for about a quarter of the company's overall sales.

As a result, the company has focused much of its expansion internationally. More than 60 percent of its new retail space was added internationally in the first quarter of this year. In the United States, the priority has been to remodel stores rather than build new ones.

Wal-Mart's not alone in enjoying substantial growth outside American borders. In its most recent quarter, Costco reported that its international segment saw a 26% increase in same-store sales, helped by stronger foreign currencies. Best Buy, too, notched impressive gains abroad, with revenue up 15%. That result was helped by a 34% increase in same-store sales in China, and a 4% climb in its Europe division. Best Buy opened its first megastore in the U.K. in April.

Even luxury's magic retailer, Coach (NYSE: COH), saw a stellar quarter overseas. The hawker of high-end handbags is planting stores across Europe this year, and it's recently added a flagship store in Shanghai. Coach reported a double-digit increase in comps in China in its just-finished quarter.

Want to find retail growth in America? Look anywhere else.

Jim Royal, Ph.D., does not own shares in any company mentioned here. Best Buy, Costco, and Wal-Mart are Motley Fool Inside Value picks. Best Buy, Coach, and Costco are Stock Advisor recommendations. Motley Fool Options has recommended a bull call spread position on Best Buy. The Fool owns shares of Best Buy and Costco. The Fool has a disclosure policy.