For nearly four years, President Trump has taken a wrecking ball to the pillars of American democracy. Though he’s done plenty of damage, they’re still standing.

But here’s the bleak reality: If Trump wins in November, many of those pillars are likely to crumble. American democracy cannot withstand four more years of Trump’s authoritarian onslaught.

The November election is not a battle between Democrats and Republicans. It’s a battle between democracy and authoritarian populism. That’s the choice on the ballot.

But we need to be clear about the threat we face. Some criticisms of Trump’s all-too-real authoritarian behavior have drifted into fantasy-land. Comparisons that equate Trump with history’s worst tyrants are ludicrous. We’re not becoming Nazi Germany. The United States, for all of its serious structural flaws, is still one of the most democratic countries in the world — even after Trump’s first term.

Trump is also a strikingly weak wannabe strongman. He pinned his campaign on building a wall on the border with Mexico, but a grand total of 16 miles of new barrier have actually been completed. He is undisciplined and incompetent, which undercuts his autocratic ambitions.

But that doesn’t diminish the Trumpian threat. Democracies are like sandcastles. Sometimes they are swept away in a single big wave, as with a coup or a revolution. But these days, authoritarian populism tends to erode democracy gradually, one piece at a time. In countries such as Hungary and Turkey, it took years, even decades, for authoritarian leaders to wear away democratic institutions.

Eventually, they succeeded. The trappings of democracy remain. But elections aren’t fair. The rule of law is a political weapon. Checks on executive power are increasingly meaningless. Political scientists call such governments “competitive authoritarian regimes,” meaning that they are effectively counterfeit democracies, semi-autocratic regimes masquerading as something they are not.

Trump has already done immense damage to U.S. democracy. He has effectively neutralized congressional oversight of the presidency because his own party refuses to hold him accountable. The White House routinely ignores subpoenas, despite overwhelming evidence of criminality around the president. His enablers are systematically purging inspectors general, who are supposed to be the referees of many democratic institutions. And Trump’s attempts to trade crucial aspects of U.S. foreign policy in exchange for help damaging his political opponents left him with the historic blemish of impeachment but no real consequences. He got away with it.

Much of the damage that Trump has done so far is intangible — yet still destructive. Democracy requires a shared sense of reality. He has subverted it by pumping lies, disinformation and conspiracy theories into our information pipeline. And chillingly, Trump has convinced millions of people to cheer for him as he attacks the very institutions that separate democratic governments from authoritarian ones. More than half of Republican voters now say the free press is “the enemy of the people,” a phrase so incendiary that Nikita Khrushchev insisted it be removed from Soviet propaganda in 1956.

A second Trump term would be much more destructive. If he wins in November, Trump will be unshackled from the biggest check of all: the electorate. He will also face weaker pushback from the judiciary, which he has packed with unqualified judges who routinely rule against basic democratic values such as voting rights.

That will give him latitude to start acting on the threats he has routinely made throughout his first term. We could see him acting far more aggressively to prosecute political opponents, pardon his criminal cronies, blacklist journalists who criticize him and revoke media broadcast licenses. He could step up his efforts to purge scientific experts who dare correct him, to politicize law enforcement and to accelerate the expansion of executive power. His recent attempts to sabotage the post office while encouraging supporters to commit a felony by voting twice in this year’s election offer a preview of his likely behavior before the 2022 midterms. And most disturbingly, his frequent encouragement of political violence could easily lead to widespread bloodshed.

In foreign affairs, he could make good on his threat to withdraw from NATO, while more closely aligning America with the foreign dictators he frequently praises.

American democracy was in decline before Trump, so he is not exclusively to blame. There are long-standing structural flaws, such as the electoral college, gerrymandering, campaign spending gone wild, voter suppression and lobbying that too often equates to political corruption. Our democratic sandcastle needed serious repairs before Trump. Yet if we give him another four years, it risks being washed away altogether.

This isn’t a normal election. It’s an emergency. In American elections before Trump, both candidates believed firmly in democracy. This year is different.

You may disagree with Joe Biden on health care, taxes or foreign policy. But if you believe in democracy, you agree with him on the thing that matters most this year: a shared commitment to protect and preserve the Republic.

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