Over the past two decades, we have witnessed escalating popular mistrust of electoral outcomes, fed by sore-loser candidates and partisan pundits. The riot at the Capitol shows what it looks like when that mistrust bubbles over. Consider: When is mistrust the highest? When people feel that the rules of the game have been changed on them.

This happened on both sides with the Florida recount in 2000: Republicans complained that the Florida supreme court was rewriting Florida statutory law after Election Day, and Democrats were upset that the election was decided in the courts (never mind how they got there). Donald Trump’s toxic feeding of mistrust remains dangerous and inexcusable, but consider why he found such fertile ground for it: because voting looked so different in 2020, with a massive shift to mail-in balloting and multiple states and localities rewriting their voting procedures, often late in the game and often without involving their state legislatures. The more people feel that a process lacks the legitimacy of long pedigree, the less likely they are to accept its outcomes as binding over their own preferences.

This ought to be a cautionary tale for progressives bent on reworking the system to accomplish more victories. It is one thing to identify groups of citizens who are barred from voting, and ensure that they can vote if they take the same efforts as everybody else. It is entirely another to clear-cut the existing rules for registration and balloting, to drastically restructure who is responsible for running elections, or even to bulldoze the Electoral College and the Senate and other longstanding processes. “Trust the rules, we just rewrote them” is a far less persuasive argument. When the storm blows hottest, it is the trees with the deepest roots that hold their ground.