It was a shocking and unprecedented week in American history. A violent mob — orchestrated by the president of the United States and his allies — overran and desecrated the U.S. Capitol, contributing to at least five deaths, including a Capitol police officer, and temporarily halted the count of electoral college votes.

Yet, later that evening, the House and Senate resumed their constitutional duty to count the electoral votes — finalizing the election of Joe Biden and Kamala D. Harris at about 3 a.m.

Here are three takeaways from the events of last week.

Bending weak institutions, breaking strong norms

For weeks in the aftermath of the November election, President Trump refused to accept defeat, pushing every button he could think of to try to overturn the results. After dozens of failed court challenges, Trump more than once pressured Vice President Pence to break the law that governs the counting of electoral votes. Trump pushed Pence to throw out enough Biden-Harris votes to overturn the election. Pence refused, several times.

Trump’s allies on Capitol Hill also vowed to object to several electoral slates already certified by the states. Sen. Ted Cruz (R-Tex.) rallied a dozen GOP senators, advocating for delaying the count until a congressionally mandated, 10-day audit of the vote could be completed.

At noon on Jan. 6, still pushing to overturn the results, Trump spoke to supporters who had gathered on the Ellipsis. His 70-minute speech, many believe, further incited his supporters to march to the Capitol, to prevent Congress from counting the electoral votes. That armed insurrection delayed, but ultimately failed to deter, Congress from affirming Biden and Harris’s election.

In some ways, a broad array of electoral institutions survived an extreme stress test. None of the efforts to subvert those rules — even mob violence — directly succeeded. To be sure, with a Democratic majority in the House and a fractured Republican Party, Trump’s supporters had virtually no chance to secure the bicameral majorities they needed to throw out electoral votes.

Even if the rules of the game proved resilient, Trump and allies trampled core norms of democratic governance that undergird such resilience: tolerance of the political opposition and respect for and protection of the peaceful transfer of power. Trump and GOP allies convinced millions of Republicans that Democrats stole the election — even as Republicans on the same ballot won seats in the House — and incited them to come to Washington to seize the seat of representative government.

Under literal and physical attack, how did the scaffolding of congressional institutions not visibly crack? Occam’s razor: A modicum of Republicans finally broke with Trump to join every Democrat in rejecting the president’s corrupt schemes that had unleashed a violent mob banging on the chamber doors. In the future, a closer election, a different constellation of party power, or a more sophisticated and even more deadly attack might buckle those institutions.

Do we now have a ‘sedition caucus’?

When lawmakers returned to their chambers later that night, they eventually cast two votes objecting to counting the certified votes from Arizona and Pennsylvania.

These two votes reveal a badly fractured Republican Party, especially in the House. Just five GOP senators sided with Trump to reject both states’ ballots; six objected only to Arizona’s, seven opposed Pennsylvania’s. But across the Capitol, two-thirds of House Republicans (139 members) favored rejecting at least one of those states’ electoral votes. Just under 60 percent (120 members) voted to overturn both states’ votes. Every House and Senate Democrat voted to uphold the results.

Dubbed the “Sedition Caucus,” House members siding with Trump hailed from disproportionately red territory. The bigger the Trump base back home, the more likely Republicans were to object to one or both slates. And vice versa: GOP lawmakers from swingier districts tended to break with Trump. Notably, taking account of lawmakers’ own electoral margins in November tells us little about how they voted on the electoral votes.

GOP cleavages also divided party leaders. Top GOP Senate leaders stuck together to uphold the certified votes, probably helping to isolate the renegade GOP who sided with Trump. What’s more, Majority Leader Mitch McConnell (R-Ky.) probably provided some cover for Kentucky legislators in the House, who overwhelmingly broke with the president regardless of their district’s partisanship.

In contrast, House Minority Leader Kevin McCarthy (R-Calif.) led the Sedition Caucus. He attracted the votes of seven of his state’s 10 Republican lawmakers, even though Trump on average secured just about half of the popular vote across the California districts the GOP won this past November. Even Rep. Mike Garcia — from California’s 25th district, a swing district won by Biden — joined the Sedition Caucus.

Here’s what this means: Over half of the House GOP continue to tether their political fortunes to Trump, reflecting that lawmakers are invariably single-minded seekers of reelection. More surprising is the votes took place after the violent insurrection. What’s more, the House vote at 3:08 a.m. to reject Pennsylvania’s slate picked up 18 GOPs who had not voted to reject Arizona’s slate on the earlier roll call — even though members surely knew that just six senators supported the challenge.

Lawmakers (just barely) avoided violence

Less appreciated was the fisticuffs that nearly broke out on the House floor at 2 a.m. When Rep. Conor Lamb (D-Pa.) admonished GOP colleagues for repeating the president’s lies that the election had been stolen, Rep. H. Morgan Griffith (R-Va.) sought to strike Lamb’s words from the record. The effort failed, a scrum broke out, and a dozen legislators converged to intervene and defuse the tension.

Before the Civil War, violence used to be common on the floors of Congress. As historian Joanne Freeman noted, some people on Twitter praised their representatives, reminding us congressional rhetoric both magnifies sentiment in the electorate and can be contagious beyond the Capitol.

Congressional leaders are already turning their attention to the many causes of the day’s security failures. But what will be harder to fix than broken glass and doors is the deeper damage to what the Capitol symbolizes, and to those who work there.

Next steps

To hold the president accountable for inciting the insurrection at the Capitol, House Democrats plan to move forward this week with a vote to impeach the president. It remains unclear when the Senate would hold a trial — or whether two-thirds of the Senate would convict.

Even in light of last week’s violent insurrection, most Republicans seem reluctant to break with the president. But Rep. Adam Kinzinger (R- Ill.) has called for removal through the 25th Amendment, and GOP Sens. Lisa Murkowski of Alaska and Patrick J. Toomey of Pennsylvania have called on the president to resign. More GOP may yet defect — or not — as they gauge the electoral strength of the Trump brand in the weeks and months to come.