When Americans debate the "elections of change" of the 20th century, there are certain dates that immediately come to mind: 1932, 1976, 1980. Maybe even 1992.

In each case, the definition is roughly the same. "Elections of change" are moments of public rebellion. The winning candidates are tapped as torchbearers, opponents of Old Washington and its insider customs. They offer new direction, a way forward, a break with the past, and the voters offer their endorsement.

But the tendency to associate election-year frustration with actual political change can be misleading and inaccurate, for two simple reasons. Rosy promises, as many Americans know, often vanish at the stump. And real reform, perversely enough, has a long history of being unplanned and unintended.

As an example of the first scenario, there is President Ronald Reagan and the election of 1980. By many appraisals, Reagan was the architect of a smaller, more efficient form of government. In his 1981 inaugural address, he spoke famously of curbing "the size and influence of the federal establishment." His re-election all but legitimized the claim. But data suggest otherwise. From 1981 to 1989, according to the U.S. Office of Personnel Management, the size of the federal civilian payroll grew by 40 percent and 200,000 people.

Flip-flop. On the other side is a president like Franklin Delano Roosevelt, a man who dramatically expanded the federal government's purview despite having no initial intention of doing so. In his 1932 nomination speech, Roosevelt, sounding more like a prescient President Reagan, told the crowd, "For three long years I have been going up and down this country preaching that government—federal and state and local—costs too much. I shall not stop that preaching." The deepening Depression changedhis mind.