You hear it every four years: This is the most important election in a generation. So if I say it to you about 2012, you’ll probably tune me out as just another hyperbolic pundit. Which is why I’ll make it more specific: For the future of America’s two political parties, this is the most important election in a generation.

The 2008 election was consequential, of course. It decided which president would respond to the worst financial crisis since the Great Depression, which led to a lot of comparisons between the 2008 election and 1932. Most famously, Time magazine photoshopped President Obama’s face onto an iconic shot of a grinning Franklin Delano Roosevelt, with the headline: “The New New Deal.” Today, a similar cover might put Obama in a tent city and ask, “The next Hoover?”

In reality, Obama didn’t enter office at the right time to be FDR or Hoover. FDR was inaugurated in 1933 — more than three years into the Great Depression. The year before he took office, the country’s economy contracted by more than 13 percent and unemployment reached 23.6 percent. The suffering was pinned on his predecessor, and it had gone on long enough that a boom was in the offing — a boom that came, right on schedule, in 1934, when the economy grew by more than 10 percent. No wonder FDR was grinning.

Obama, by contrast, entered office as the crisis was peaking. The worst period of the crisis would prove to be the fourth quarter of 2008 and the first quarter of 2009, which mostly passed before Obama assumed the presidency, but which only showed up in the unemployment numbers months later. By the end of 2009, the Obama administration and the Federal Reserve had the economy growing again. But the damage done in 2008 and early 2009, which shot unemployment to 10 percent, nevertheless manifested on his watch.

So the administration is betwixt and between: According to an August Associated Press poll, a majority of Americans still blame George W. Bush for the economic crisis. So Obama isn’t Hoover. But according to every poll conducted in recent months, a majority of Americans don’t think Obama has turned this thing around, so he’s not FDR, either. The next president, however, might be.

The pat story behind FDR’s victory and the ensuing decades of mostly Democratic dominance is that the president got the policy right and the politics followed. Whatever you believe about FDR’s policies, a more international perspective will disabuse you of the notion that the golden age for the Democratic Party was an ideological triumph rather than an accident of history. As Larry Bartels, a political scientist at Vanderbilt University, has written, globally, the pattern is clear: Whichever party was in power when the Great Depression hit was booted out of office, and whichever party was in power when the global recovery took hold reaped huge political benefits.

“In the U.S.,” wrote Bartels, “voters replaced Republicans with Democrats and the economy improved. In Britain and Australia, voters replaced Labor governments with conservatives and the economy improved. In Sweden, voters replaced Conservatives with Liberals, then with Social Democrats, and the economy improved.

“In the Canadian agricultural province of Saskatchewan, voters replaced Conservatives with Socialists and the economy improved. In the adjacent agricultural province of Alberta, voters replaced a socialist party with a right-leaning funny-money party created from scratch by a charismatic radio preacher . . . and the economy improved.

“In Weimar Germany, where economic distress was deeper and longer-lasting, voters rejected all of the mainstream parties, the Nazis seized power, and the economy improved. In every case, the party that happened to be in power when the Depression eased dominated politics for a decade or more thereafter.”

The 2008 economic crisis was not nearly so deep as the Great Depression — in part because of an aggressive policy response — and so the recovery is not likely to be so remarkable, nor the political benefits so dramatic. But they’re still likely to be present. And because a recovery is likely within five years — if it doesn’t happen, we’re sunk — whichever party wins the White House in 2012 is likely to get the credit, and so too will its policy agenda.

“Imagine someone like Rick Perry gets in and makes very dramatic changes in policy, like repealing health-care reform,” says Seth Masket, a political scientist at the University of Denver, “and then the next year the economy improves for reasons not related to the policies. Those policy shifts will nevertheless get the credit. And Obama’s approach will be discredited for a very long time.”

The 2008 election was crucial for enacting economic and social policy. The 2000 election reshaped U.S. foreign policy for a decade. But the 2012 election is likely to be the one that matters for ratifying policy and for gaining the majorities needed to make it for a long time to come — comparable, perhaps, to the 1980 election, when Ronald Reagan and the GOP benefited dramatically from Fed chief Paul Volcker’s success in crushing inflation.

Does that make 2012 the most important election in a generation? For the country, it’s hard to say. For the two political parties, yes. Yes, it does.