The best analogy to Donald Trump in 2017 is George W. Bush in 2005

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President George W. Bush speaks at a conversation about Social Security in Louisville, Kentucky, March 10, 2005.

We are living through unusual times, and the tendency is to reach for extreme historical analogies. I have seen this era compared to the run-up to the Civil War, to Watergate, to the dawn of Nazi Germany, to the presidency of Andrew Jackson, to the rise of Italy's Silvio Berlusconi, to the fall of the Roman Empire.

But the most persuasive analogue is nearer both in time and in space. What this period most closely resembles, argues political scientist Brendan Nyhan, is the aftermath of the 2004 election, when George W. Bush defeated John Kerry. Then, like now, a culturally polarizing Republican candidate was narrowly elected after a campaign waged atop nationalistic, identitarian appeals. Then, like now, the GOP gained control of both the White House and Congress. Then, like now, the winner had no clear policy mandate, and quickly suffered massive legislative defeat (Social Security privatization for Bush, Obamacare repeal for Trump). Then, like now, the president watched his favorability ratings tumble into the 30s, and appeared to be headed for a severe backlash in the midterms.

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I would take the analogy yet further. Trump's callousness and indiscipline has left many liberals yearning for Bush's more dignified and decent bearing. A poll in October found that a majority of Democrats now hold a favorable opinion of the 43rd president. But in 2004, Democrats absorbed Bush's reelection as more than a defeat; it was a cultural rejection and a political crisis. Democrats warned that it was "the most important election of our lifetime." If John Kerry didn't win, the results could be, would be, catastrophic.

But Bush crushed Democrats with a campaign that, as Robert Reich wrote, was "not just God and gays but also true grit in fighting the evils of Saddam Hussein and global terrorism." This was the age in which Bill Clinton warned that "when people are insecure, they'd rather have somebody who is strong and wrong than someone who's weak and right," the era of flag pins, of Swift Boat Veterans, of books with titles like Bush Country: How Dubya Became a Great President While Driving Liberals Insane.It was the era of anti-gay marriage ballot initiatives, of Democrats panicking over the loss of white Christian voters.

When Bush won, the left absorbed it as a trauma — proof that they had lost touch with the heartland, that they no longer understood the country they called home. The 2004 election, wrote Paul Starr in the liberal American Prospect, confirmed that Democrats were "no longer a majority party." In the same magazine, Alan Brinkley wrote, "the greatest success of the modern right has been transforming conservatism into a populist phenomenon."

Sound familiar? Just wait. In the New York Times, the headline was, "Baffled in Loss, Democrats Seek Road Forward." The article records a litany of prominent Democrats unloading their fears and their confusion. "We need to be a party that stands for more than the sum of our resentments," said Evan Bayh, an Indiana Democrat then in the Senate. "In the heartland, where I am from, there are doubts. Too often, we're caricatured as a bicoastal cultural elite that is condescending at best and contemptuous at worst to the values that Americans hold in their daily lives."

All of this could have been said by, and written, about, Democrats in the aftermath of 2016. And it yields, I think, a few lessons.

What 2004 teaches us about 2016

Today, 2004 is one of the few elections I know of that many Democrats believe it's better that they lost. Had they won, it would have been President John Kerry facing a Republican Congress, managing the flailing Iraq War, and ultimately blindsided by the financial crisis. The congressional majorities Democrats built in 2006 and then expanded on in 2008 — the majorities that permitted the passage of the Affordable Care Act and the stimulus and much else — would never have materialized. Bush's continued presence in office meant Republicans paid the political price for their past mistakes, and Democrats reaped the rewards.

A similar future is plausible, though far from assured, today. With the important exception of replacing Justice Antonin Scalia with Neil Gorsuch, Trump and the Republican Congress appear to be getting less done, and paying more of a political price, than most expected. It seems possible now that Democrat Doug Jones will win Jeff Sessions' Senate seat in Alabama; if that happens, retaking both the House and the Senate is well within reach for Democrats in 2018, putting an end to Trump's legislative agenda.

If Trump's presidency continues to flail — to say nothing of if there's a recession or a poorly managed foreign crisis — it's easy to imagine a Democrat beating him in 2020 and entering office with massive congressional majorities, setting up, again, a period of sweeping progressive governance. The downballot gains could also lead to more Democratic statehouses before the next Census, which would in turn mean less Republican gerrymandering, and a significantly improved House outlook for Democrats through 2030.

The cultural forces Trump represents also seem weakened by his ascent. Opinions towards trade and immigration have swung sharply towards the left since Trump's election, and the acceptance of sexual harassment that Trump's win seemed to suggest has been overwhelmed by the stunning power of the #MeToo movement.

Which is all to say that one lesson of the post-2004 moment is low ebbs in political power sometimes set up massive gains in political power, particularly when the governing party governs poorly. Just as Democrats regret Bush's second term less, and Republicans regret it more, than either side expected at the time, the same could well prove true of Trump — particularly if the loathing he inspires among younger voters hardens into a persistent distaste for the GOP.

Another lesson is that the path back to power often looks very different from what the post-election analyses suggest. The Democrats agonizing over evangelical heartland voters and whether they had any candidates who looked natural holding a hunting rifle did not think their resurgence lay with a cosmopolitan, liberal African-American whose name rhymed with "Osama." But it did.

The same is true for Republicans who worried over Barack Obama's victories and the rising Democratic majority. Readers of the GOP's post-2012 "autopsy" report know that the party expected it would be a candidate with Marco Rubio's profile that led them back to the majority. "We need to campaign among Hispanic, black, Asian, and gay Americans and demonstrate we care about them, too. We must recruit more candidates who come from minority communities," warned the party that would soon nominate Donald Trump and win back the White House.

It's a mistake to think that the only way to win an election is to win over your opponent's coalition, rather than creating a new version of your own. For all the debates about the white working class and identity politics currently roiling the Democratic Party, my guess is if Democrats are successful in 2020, it will be with a candidate who transcends these arguments rather than one who embodies them.

But the most important lesson is that the story of American politics is ongoing and unpredictable. We tend to take elections as the closing of chapters, as statements about what America really believes and where we are truly going. But they're anything but. In 2004, Democrats could not imagine where they would be in 2008. In 2014, no one believed Donald Trump would be president today — including Donald Trump. History shows American politics is often far from what it seems, and you don't need to reach long into our past for examples.

Commentary by Ezra Klein, editor-at-large, co-founder at Vox. Follow him on Twitter @ezraklein.

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