Lynn O'Shaughnessy

It wouldn't be a stretch to say that most of the planet has gone gaga over the World Cup, which has brought together 32 of the globe's best soccer teams to compete in a thrilling blur of sweat-soaked matches.

The Brazilian government temporarily changed the country's banking hours so people could watch the games and still deposit their paychecks. In Mexico, tens of thousands of fans have jammed city squares to watch games on jumbo televisions. In Bangladesh, students at one university threatened to riot if the administration didn't delay final exams until the World Cup ended. And the Bangladesh team isn't even in the tournament.

But in the United States, the monthlong athletic drama is as stimulating as two Dramamine tablets and a glass of water. When my husband and a friend tried to catch the opening lunchtime match at a sports bar, the TVs were tuned to golf and tennis. When the manager was asked why the World Cup game wasn't on, he replied, "What's the World Cup?" A televised bass fishing tourney would have trumped airing the planet's greatest sporting event.

Perhaps Americans have dismissed soccer because we aren't good at the sport. After all, in many other countries, children know how to dribble the ball at an age when our kids are developing a taste for Happy Meals. Or maybe it's because we only like to play homegrown sports. Why should we learn to appreciate soccer's finesse moves when we can watch 400-pound linebackers crack each other's skulls and then critique the beer commercials?

This sort of parochialism might explain why many Americans are just as reluctant to invest overseas. Why venture abroad when we can invest in Microsoft, Coca-Cola, Nike and countless other homegrown success stories? But clinging to this sort of myopia can ultimately hurt your financial bottom line.

There are two excellent reasons why you should add a dash of international picante to your portfolios. By doing so, you can potentially enhance your returns, while at the same time reduce the sort of harrowing, unpredictable market volatility that too often triggers investor stampedes into bank lobbies for the safety of CDs.

If you stick with a buy-America investing approach, you're betting all your chips on one roulette number. And often, you won't fare as well as you might expect. To illustrate, here's an example from the Schwab Center for Investment Research: From 1970 to 2005, the U.S. market failed to rank as the top performing developed market for even one year.

Lynn O'Shaughnessy

Lynn O'Shaughnessy is the author of Retirement Bible.

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