It's a sign of these unsettled times that the analyst who famously announced "the end of history" in 1989, when the Soviet empire was crumbling and liberal, free-market democracy seemed inevitable, has just published a new essay with the provocative title "The Future of History."

Francis Fukuyama's article appears in the January edition of the journal Foreign Affairs. It offers a good introduction to what may be the biggest political issue of 2012 -- the decline of the middle class in the United States and around the world. Without this middle class, Fukuyama argues, liberal democracy loses its anchor.

"Protect the middle class" is a rote slogan for both parties in this presidential election year. But Fukuyama argues that the danger comes not from particular tax or spending policies of either party, but from the very dynamic of the modern, global economy. This new world may be flat, but it's also tilted -- with the benefits flowing disproportionately toward the elites.

"Inequality has always existed, as a result of natural differences in talent and character," writes Fukuyama. "But today's technological world vastly magnifies those differences." The fortunate few "can become financial wizards or software engineers and take home ever-larger proportions of the national wealth."

Fukuyama is a useful bellwether. "The End of History" was widely cited as the apogee of post-Cold War optimism, and then derided after Sept. 11, 2001, when history seemed to have returned with a vengeance.

Fukuyama isn't revising his enthusiasm for liberal democracy, which he still sees as "the default ideology around much of the world today." Instead, he's questioning whether the global market may be the enemy of liberal democracy, rather than its handmaiden. In 1989, he saw the technology-driven global marketplace -- and its ever-spreading wealth -- as a crucial reason for "the end of history" and the universal embrace of democratic values. Now, he worries that globalization is eroding the middle classes that are, historically, the bulwark of a liberal political order.

Fukuyama sees rising anger among middle-class Americans toward Wall Street. But he notes the paradox that the chief beneficiary has been the tea party movement that endorses the corporate status quo, rather than the Occupy protesters who challenge it. As Campaign 2012 begins for real, the core question is the economy. The public is angry at Wall Street elites who seem to be gaming the system. Every candidate has a multitiered plan for economic renewal. What's missing is a formula for breaking the national political deadlock so that any such program can be enacted.

Fukuyama notes: "Many people currently admire the Chinese system not just for its economic record but also because it can make large, complex decisions quickly, compared with the agonizing policy paralysis that has struck both the United States and Europe in the past few years."

That's a warning sign -- when people look to a totalitarian state for a system that works.