For the past year, President Biden has tried to be his old, bipartisan, “we can all get along” self.

He ignored his authoritarian predecessor and the lies he continued to spread about the 2020 election. He went out of his way to construct an infrastructure bill that could draw Republican support and hoped to accomplish more in partnership with the opposition. He desperately wanted the country and Washington to return to being what they were when he was first elected to the Senate in 1972.

On Thursday, Biden finally said: Enough.

Marking the anniversary of the Jan. 6 attack on the Capitol, the president ripped into Donald Trump’s subversion of democracy and the refusal of most Republicans to stand up to the former president’s lies. In what was by far the most passionate, forceful and effective speech of his presidency, he moved democracy to the center of the nation’s political debate.

“You cannot love your country only when you win,” Biden declared. “You can’t obey the law only when it’s convenient. You can’t be patriotic when you embrace and enable lies.”

“It is up to all of us, to we, the people, to stand for the rule of law, to preserve the flame of democracy,” he insisted. “To keep the promise of America alive. That promise is at risk, targeted by the forces that value brute strength over the sanctity of democracy. … Make no mistake about it, we’re living at an inflection point in history both at home and abroad.”

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It was an inflection point for Biden’s presidency as well. He acknowledged as clearly as he ever has that the Republican Party is no longer the constructive force in our politics that he often worked with as a senator and vice president.

True, the president praised “some courageous men and women in the Republican Party … standing against” Trump’s lies. He always has been ready to work with those who hold “a shared belief in democracy.” Then he dropped the hammer on the rest of the GOP.

“Too many others are transforming that party into something else,” he said. “They seem no longer to want to be the party of Lincoln, Eisenhower, Reagan, the Bushes.”

“At this moment, we must decide: What kind of nation are we going to be? Are we going to be a nation that accepts political violence as a norm? Are we going to be a nation where we allow partisan election officials to overturn the legally expressed will of the people? Are we going to be a nation that lives not by the light of the truth but in the shadow of lies?”

Speaking in the rotunda of the building vandalized by Trump supporters who wielded weapons, assaulted police officers, and rifled desks and shattered windows , Biden rebuked the “former president” 16 times in the address without ever naming him. At one point, he sharply refined that formulation by saying: “He is not just the former president. He is a defeated former president. Defeated by a margin of over 7 million of your votes.”

And he did not hold back in describing what Trump has been doing:

“The former president of the United States of America has created and spread a web of lies about the 2020 election. He has done so because he values power over principle. Because he sees his own interest as more important than his country’s interest, than America’s interest. And because his bruised ego matters more to him than our democracy or our Constitution. He can’t accept he lost.”

Only rarely does a single speech alter the trajectory of politics, and Thursday’s address will matter even more if he and Vice President Harris follow up with equal force when they speak next week in Atlanta on behalf of voting rights — and if the administration fully joins the battle for two democracy bills pending in the Senate.

But in one important moment of truth-telling, Biden changed the direction of his presidency by setting his face against a denialism that has distorted our nation’s debate since the day he was inaugurated. He insisted that Republicans could not be treated as a normal opposition as long as most of them — in their leadership and in their ranks — refuse to break unreservedly with an odious, democracy-wrecking liar.

When Biden was asked by a reporter as he left the Capitol whether his address had been “divisive,” he did not back down. “To heal,” he said, “you have to recognize the extent of the wound. You can’t pretend.”

Biden chose the anniversary of one the grimmest days in U.S. history as the occasion to declare that the politics of pretending are over.