In our research, we argue that though all democracies are imperfect, one of their central virtues is that they are built to be resilient — to bend without breaking, even when elected leaders pull institutions in an authoritarian direction. But just because they’re more flexible doesn’t mean democracies can’t break. Resilience — the ability to adapt and keep functioning under strain — is a resource that needs replenishing, not a guarantee of safe passage.

It’s normal for institutions to face challenges from events or from politicians who try to use them for their own purposes. When institutions survive a stress test, they may come out stronger or weaker. Ambiguous laws can be clarified to withstand abuse; regulations can be updated; and public officials gain experience in how to prevent or defend against future tests. But it can take time for the strengthening to occur.

The 2020 election provides a clear example of democratic resilience to authoritarian pressure. Election officials and judges fielding legal challenges had to adapt not only to the enormous logistical challenges of the pandemic but also to Mr. Trump’s rhetoric. His attacks — and those from elected officials in his party and from the conservative media — put additional pressure on election officials and poll workers, who faced threats, intimidation efforts and overt pressure to ignore the will of the voters.

Yet in most of the more than 10,000 electoral jurisdictions across the country, voters cast ballots without incident and Election Day was peaceful. International election observers praised the election as orderly and organized.

Both democracy optimists and pessimists can draw the conclusions they want to see from this example. Optimists can say that our election system faced the 2020 test admirably, and those who run it will be better prepared for future efforts to undermine their work. Pessimists can say that Mr. Trump’s attacks will leave lasting scars. Next time, election officials might give in to political pressure. Or the damage might be invisible, like a tree’s weakened root system, deterring people from running for office or working at the polls.