The insurrection at the US Capitol was both stunning and predictable, the result of a Republican Party that has repeatedly enabled Donald Trump’s destructive behaviour.

When he was a presidential candidate in 2016, Republican officials ignored his call to supporters to “knock the crap out” of protesters.

Less than a year after he took office, party leaders argued he was taken out of context when he said there were “very fine people” on both sides of a deadly white supremacist rally.

Last summer, most party leaders looked the other way when he had hundreds of peaceful protesters forcibly removed from a demonstration near the White House so he could pose with a Bible in front of a church.

But the violent siege on Capitol Hill offers a new, and perhaps final, moment of reckoning for the Republican party. The usual excuses for Mr Trump — he is not a typical politician and is uninterested in Washington’s niceties — fell short against images of mobs occupying some of American democracy’s most sacred spaces.

The party, which has been defined over the past four years by its loyalty to Mr Trump, began recalibrating in the aftermath of Wednesday’s chaos.

One of his closest allies in Congress, senator Lindsey Graham, said “enough is enough”.

Representative Nancy Mace said Mr Trump’s accomplishments in office “were wiped out today”.

Stephanie Grisham, the first lady’s chief of staff and a former White House press secretary, submitted her resignation, but declined to say what has prompted her move.

Deputy national security adviser Matt Pottinger, White House social secretary Rickie Niceta and deputy press secretary Sarah Matthews also resigned, according to officials.

For the party to move forward, it will need to grapple with the reality that Mr Trump lost to Joe Biden by more than seven million votes and a 306-232 margin in the electoral college.

Former Republican president George W Bush described the violent mob as “a sickening and heartbreaking sight”.

He declined to call out Mr Trump or his allies, but the implication was clear when Mr Bush said the siege “was undertaken by people whose passions have been inflamed by falsehoods and false hopes”.

Representative Liz Cheney, a senior House Republican and the daughter of Mr Bush’s vice president, was much more direct in an interview on Fox News.

“There’s no question the president formed the mob. The president incited the mob,” she said. “He lit the flame.”

While their criticism was searing, Mr Bush and Ms Cheney had already been among a small group of Republican officials willing to condemn Mr Trump’s most outrageous behaviour at times. The overwhelming majority of the party has been far more reserved, eager to keep Mr Trump’s fiery base on their side.

His grip on his party appeared weakened when members of Congress returned to the Capitol on Wednesday night, having spent several hours hiding in secure locations after being evacuated.

Before they left, a handful of Republican senators and more than 100 Republican House members were set to oppose the vote to certify Mr Biden’s presidential victory.

It was led by senators Ted Cruz and Josh Hawley, each with his own 2024 presidential ambitions, over the objection of Senate majority Leader Mitch McConnell, who warned that that US democracy “would enter a death spiral” if Congress rejected state election results.

When they resumed debate, however, much of the energy behind the extraordinary push had fizzled out. Several Republicans dropped their objections. Mr Hawley and Mr Cruz did not, but they offered scaled-back arguments.

Mr Hawley condemned the day’s violence but also called for an investigation into “irregularities and fraud”. Earlier in the day, his home town newspaper, the Kansas City Star, released an editorial charging that he “has blood on his hands” for enabling Mr Trump’s false claims.

Others Republicans were clearly more concerned about the day’s violence and the events that preceded them.

“Dear MAGA (Make America Great Again) – I am one of you,” former White House aide Alyssa Farah tweeted. “But I need you to hear me: the Election was NOT stolen. We lost.”

Jefferson Thomas, who led Mr Trump’s campaign in Colorado, expressed regret about joining his team in the first place, calling Wednesday’s events “an embarrassment to our country”.

“This isn’t what I ever imagined when I signed up to #MAGA. Had I known then that this is how it would end, I never would’ve joined,” he wrote on Twitter.

Mr Trump’s former secretary of defence, James Mattis, who denounced the president as a threat to the constitution last year, described the violent assault on the Capitol as “an effort to subjugate American democracy by mob rule… fomented by Mr Trump”.

“His use of the presidency to destroy trust in our election and to poison our fellow citizens has been enabled by pseudo political leaders whose names will live in infamy as profiles in cowardice,” Mr Mattis said.

Anthony Scaramucci, a former Trump aide, offered his harshest words for Mr Trump’s Republican enablers, tweeting: “Republican elected officials still supporting Trump need to be tried alongside of him for treason.”