Truth is, the idea that Russia determined the election is overstated. It would never have resonated so loudly without our deep polarization — and our structural issues, including the vast discrepancy between the popular vote in favor of Mrs. Clinton and the narrow Electoral College win for Mr. Trump.

These issues were rooted in our system and had already played out in 2000. By overplaying Russia’s ability to influence the vote, American politicians and pundits conceded victory to Russia and its intelligence agencies. Instead, we should have focused on fixing our own faults.

Today, we are even more fractured than in 2016. What was then a vulnerability is now a full-blown national security crisis.

Our partisan strife has contributed to the botched handling of the Covid-19 pandemic. It has eroded our international reputation. It has made us susceptible to manipulation by any foreign or nonstate actor that wants to weaken us. Our own political actors are undermining our democracy in a gambit to sway the election.