In front of the presidential seal, flanked by two American flags, inside the Capitol's Statuary Hall -- a rare place for a president to speak but from where pro-Trump rioters stormed last year -- Biden directly blamed Trump for last year's violence and rejected the former president's characterization of the mob as "patriots."

“Is that what you thought when you looked at the mob ransacking the Capitol, destroying property -- literally defecating in the hallways -- rifling through the desks of senators and representatives, hunting down members of Congress? Patriots? Not in my view," he said in a firm tone.

“To me, the true patriots were the more than 150 Americans who peacefully expressed their vote at the ballot box," Biden continued.

"The former president -- who lies about this election -- and the mob that attacked this Capitol could not be further away from the core American values. They want to rule or they will ruin -- ruin what our country fought for at Lexington and Concord, at Gettysburg and Omaha Beach, Seneca Falls, Selma, Alabama," he said, invoking ideals of American democracy.

Rejecting Trump’s election lies one by one, Biden repeated that despite the former president building his false case over months that there is "zero proof the election results are inaccurate."

Without mentioning Trump by name, Biden blamed him over and over again for the violence that erupted at the Capitol last year and the serious danger his "web of lies" poses to the country.

"Those who stormed this Capitol, and those who instigated and incited, and those who called on them to do so, held a dagger at the throat of America and American democracy," Biden said about Trump and his allies.

Biden hinted at how plotting to try to take the election from him -- and more so, the will of American voters -- began well in advance of Jan. 6 as Trump sewed doubt in the election with his supporters as it neared.

"They didn't come here out of patriotism or principle. They came here in rage -- not in service at American rather and service of one man. Those who incited the mob -- the real plotters -- were desperate to deny the certification of this election," Biden said.

"The former president and his supporters have decided the only way for them to win is to suppress your vote and subvert our elections, it's wrong, it's undemocratic and frankly, it's unAmerican," Biden said, appearing to speak both directly about Trump, leaning into the camera, and to the American people.

He said Americans "cannot allow ourselves" to be a kind of nation that stands for lies and by a former president that has violently rejected a peaceful transfer of power.

In his most forceful remarks yet against Trump, Biden called out the former president -- without using his name -- for weaving what he called a "web of lies" around the 2020 election and attacking American democracy as no other leader has before.

"We must be absolutely clear about what is true and what is a lie," Biden said. "And here's the truth: The former president of the United States of America has created spread a web of lies about the 2020 election. He's done so because he values power over principle -- because he sees his own interest is more important than his country's interest and America's interest -- because his bruised ego matters more to him than our democracy or our Constitution."

"He can't accept he lost," Biden said. "He can't accept he lost even though that's what 93 United States senators, his own attorney general, his own vice president, governors and state officials and every battleground state, all said, he lost."

Establishing Trump as a "defeated former president -- by a margin of 7 million votes in a free and fair election," Biden defended his win against Trump and his supporters by laying out the facts of the election.

A somber Vice President Kamala Harris, in remarks ahead of Biden, said what the "extremists who roamed these halls targeted" last year when was not only an attack on the lives of elected leaders and the 2020 election.

"What they sought to degrade and destroy was not only a building, hallowed as it is. What they were assaulting. were the institution's the values, the ideals that generations of Americans have marched, picketed, and shed blood to establish and defend," she said.

The vice president, who was at the Capitol on the morning of Jan. 6 last year, reflected on what she called "the dual nature of democracy: its fragility and its strength."

"The strength of democracy is the rule of law," she said. "And the fragility of democracy is this. That if we are not vigilant, if we do not defend it, democracy simply will not stand. It will falter and fail."

She ended her remarks with a call to pass Democrats voting rights bills in the Senate as restrictive voting laws are enacted across the country.

"But we, the American people, must also do something more. We cannot sit on the sidelines. We must unite in defense of our democracy," she said.

Biden took the oath of office just days after the violent attack on the Capitol last Jan. 6, but he has fastidiously tried to prevent those unprecedented circumstances -- or his predecessor -- from dominating his first year in the White House.

But on the anniversary of the insurrection, he confronted Trump in a direct, personal way, in some of his strongest language yet.

"We must be absolutely clear about what is true and what is a lie. And here's truth," he said, speaking from Statuary Hall in the Capitol that rioters ransacked last year. "The former president of the United States of America has created and spread a web of lies about the 2020 election. He's 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."

Click here to read a full transcript of Biden's speech.

-ABC News' Ben Gittleson and Sarah Kolinovsky