President Donald Trump incited his followers to “Fight for Trump” at a rally Wednesday morning, and they took him at his word.

When pro-Trump rioters stormed the U.S. Capitol and stopped Congress from certifying President-elect Joe Biden’s victory, the “law and order” president didn’t urge them to stand down. After all, they were just doing his bidding. He had whipped them into a frenzy with a 90-minute rant which promised that a “rigged” election would be reversed.

And after the besieged Capitol was under lockdown, with legislators huddled under desks, shots fired, and GOP leaders begging Trump to halt the insurrectionists, he released a video that only fueled the fire. “We had an election that was stolen from us,” Trump said. “But you have to go home now. ... We love you. ... I know how you feel.”

If anyone doubted the president was committing sedition, those doubts should be over. Donald J. Trump is undermining the national security of our country. He should be forced to resign.

Because let’s be clear here: The president incited this unprecedented attack. Asking him politely to stop it is like asking an arsonist to put out a massive forest fire he deliberately set, match by match.

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Trump has been insisting for months that any election he lost would be rigged. On Wednesday, as legislators gathered in the Capitol, he fired up his followers on the National Mall by repeating his whole catalog of conspiracy theories about fraud in swing states — lies that have been rebuffed over and over by recounts, state and federal courts, the Supreme Court, and state voting officials.

“We won in a landslide,” he told the mass assembled, insisting, “We will never give up.” Hint, hint. And they listened intently.

Trump promised that Vice President Mike Pence would refuse to certify the electoral votes at the joint session on Wednesday (where too many GOP legislators were ready to challenge certification in swing states — from fear of the president).

But Pence issued a statement Wednesday saying he had no constitutional power to reverse the election. No wonder Trump’s deluded followers were enraged.

It was this kind of unhinged Trump behavior that impelled all 10 living ex-U.S. secretaries of defense to issue a statement Sunday that the uniformed military must not be used to determine an election. I was told by one of the organizers that they feared the president might provoke violence, then use the Insurrection Act to call up uniformed troops to try to retain power.

Washington, D.C.’s mayor has now had to call for the National Guard. But who knows what military fantasies Trump might entertain in the coming days.

Many GOP legislators have yet to grasp reality and are totally complicit in Trump’s sedition.

House Minority Leader Kevin McCarthy told Fox News nervously, as the mob attacked the Capitol, “This is not the American way.” So what did he think he was doing when he encouraged fellow GOP House members to challenge states’ certification? He was reinforcing the delusion that Trump had won.

McCarthy told Fox he phoned Trump and urged him to make a statement. Instead, Trump defended his mob, tweeting: “These are the things and events that happen when a sacred landslide election victory is so unceremoniously & viciously stripped away.” Twitter locked his account for 12 hours for appearing to incite violence.

The damage done is not just to our democratic system at home, but to our country’s reputation abroad.

“It is disgraceful that Trump has induced this and hasn’t called on the [demonstrators] to disband,” says Stanford University’s Larry Diamond, one of the country’s top experts on democratic systems. “It makes us look like a banana republic.”

“These images will be conveyed around the world,” says Diamond. “They are doing extreme damage to the reputation of U.S. democracy. You can imagine what Russia and China will do with this.

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“It was already a gift to autocrats around the world, to see Trump and a large percentage of Congress reject the election results. This damages the image of democracy as a system, not just American democracy. It will take a long time to recover from this.”

Yet, there is something Congress can do to start repairing the damage. GOP legislators can stop participating in Trump’s continuing campaign to brainwash his base into believing the election, and Joe Biden’s presidency, are illegitimate. They can join a bipartisan delegation to demand that Trump publicly concede defeat and chastise his rioters — or else step down immediately.

As Biden put it to Trump Wednesday: Go on national television “to defend the Constitution and demand an end to this siege. ... It’s not protest. It’s insurrection.”

If Trump won’t concede defeat to his base and denounce the mob, it’s time for Pence and Congress to invoke the 25th Amendment. This is clearly a sick, if not deranged, president, who can do far more damage to our democracy if he is not immediately blocked. If, after today’s tragedy, GOP leaders are too cowardly to act, they will go down in history as wholly complicit in his crimes.