As companies seek individuals who can work anywhere in the world, plenty of U.S. business schools claim they're "going global," adding weeklong jaunts to China, Korea or Brazil and increasing the share of international students in their classes.

But that's not enough to train tomorrow's leaders, argues Pankaj Ghemawat, a professor of global strategy at IESE Business School in Barcelona. In order to prepare students for a global business environment, he says, schools must do a better job explaining globalization—and...