House Judiciary Chairman Rep. Jerry Nadler in his floor remarks said the rioters who stormed the Capitol will be brought to justice. Amid accusations from some members of Congress that other members may have abetted rioters, he said accomplices on the floor will also be held accountable.

"We will bring the rioters to justice. Their accomplices in this house will be held responsible," Nadler said. "But today we must focus on the gravest threat first: President Trump."

Rep Adam Schiff, D-Calif., who was the lead impeachment manager for Trump's last impeachment proceedings said America has endured a Civil War, world wars, the Great Depression and now "a Trumpist and white nationalist insurrection," but the nation will prevail because of those Americans patriotic enough restore it.

"This is one of those moments," Schiff said. "Enough."

Rep. James Clyburn, D-S.C., argued that while Republicans are calling for unity and healing, it was the president who refused to recognize Biden's win, leading to a violent transition of power.

"This president's refusal to participate in the peaceful transfer of power and his role in the incitement of last week's violence poses an existential threat. This threat must be extinguished immediately," Clyburn said.

Rep. Jamie Raskin, D-Md., co-sponsor of the impeachment article, warned of future threats to lawmakers if the president isn't held accountable, stressing, "Every one of us in this room right now could have died."

Rep. Jim Jordan, R-Ohio, one of the president's staunchest supporters, began the House debate for Republicans by opposing impeaching Trump and railing against Democrats for what he called their attempt to "cancel the president."

"We should be focused on bringing the nation together. Instead Democrats are going to impeach the president for a second time, one week, one week before he leaves office. Why? Why? Politics and the fact that they want to cancel the president," he said.

"Impeachment round two. It's always been about getting the president, no matter what. It's an obsession. An obsession that's now broadened. It's not just about impeachment anymore. It's about canceling," he added.

Rep. Tom McClintock, R-Calif., told the chamber, "I cannot think of a more petty, vindictive and gratuitous act than to impeach an already defeated president a week before he is to leave office."

"President-elect Biden's promise to heal the nation becomes a hollow mockery in the harsh reality of this unconstitutional act," he said.

Biden and Vice President-elect Kamala Harris have deflected when asked questions about impeachment, saying the decision is with Congress.

After the House Reading Clerk concluded reading the full impeachment resolution against President Trump, the House has proceeded with the session by kicking off two hours of debate on the article on impeachment charging Trump with inciting an insurrection. House Speaker Nancy Pelosi was the first to deliver remarks and called Trump “a clear and present danger” to the country.

"The president of the United States incited this insurrection, this armed rebellion, against our common country. He must go. He is a clear and present danger to the nation that we all love," Pelosi said. "Since the presidential election in November, an election the president lost, he has repeatedly lied about the outcome, sowed self-serving doubt about democracy and unconstitutionally sought to influence state officials to repeal reality."

"My fellow members, my fellow Americans, we cannot escape history. Let us embrace our duty, fulfill our oath, and honor the trust of our nation. And we pray that God will continue to bless America," she added, calling on the House to vote to impeach Trump and for the Senate to vote to convict him.

A spokesperson for Pelosi confirmed to ABC News she is wearing same outfit Wednesday that she wore for Trump's last impeachment vote on Dec. 18, 2019.

-ABC News' Benjamin Siegel

House Reading Clerk Susan Cole, donning an American flag mask, recited the article of impeachment before two horus of debate on the resolution kicked off.

Democrats formally introduced an impeachment resolution Monday, charging Trump with "incitement of insurrection" after he told his supporters at a “Save America Rally” to march on the Capitol during Congress’ joint session to count Electoral College votes on Jan. 6.

"In all this, President Trump gravely endangered the security of the United States and its institutions of Government. He threatened the integrity of the democratic system, interfered with the peaceful transition of power, and imperiled a coequal branch of Government. He thereby betrayed his trust as President, to the manifest injury of the people of the United States," Cole read aloud from the measure.

The impeachment article also cited Trump's call with the Georgia Republican secretary of state where he urged him to "find" enough votes for Trump to win the state -- along with the Constitution's 14th Amendment, noting that it "prohibits any person who has 'engaged in insurrection or rebellion against' the United States" from holding office.

At the top of his remarks in Alamo, Texas, after making brief comments about the strength of the border wall, the president addressed the riot at the Capitol -- remarking that it “has been a difficult year and a difficult election."

“Free speech is under assault like never before,” Trump said -- calling the latest impeachment effort a "hoax" but threatening the efforts to remove him from office could haunt Biden.

“The 25th Amendment is of zero risk to me, but will come back to haunt Joe Biden and the Biden administration," Trump said. "As the expression goes, 'Be careful what you wish for."'

“Millions of our citizens watched last Wednesday as a mob stormed the Capitol and trashed the halls of government. As I have consistently said throughout my administration, we believe in respecting America’s history and traditions -- not tearing them down,” Trump said, reading from a teleprompter.

“We believe in the rule of law, not violence or rioting," he said, going on to describe the pandemic landscape. "This has been a difficult year and a very difficult election. The pandemic has made it a very, very difficult year for our country and virtually every country around the world. Now is the time for our nation to heal -- it is the time for peace and calm."

“Respect for law and law enforcement -- so many are here -- is the foundation of the MAGA agenda, and we are a nation of law and order. That is why we are here today: to talk about what we must do to uphold the rule of law in America and how we must continue to support our law enforcement heroes, which is exactly what you are," Trump said.

At the same time as Trump spoke, acting U.S. Attorney in the District of Columbia Michael Sherwin announced that more serious indictments against some already charged in the violent Capitol siege were imminent and said there were "pipe bombs" found outside the Capitol Wednesday.

Before Tump's remarks, Trump walked slowly to the border wall, lined with American flags. He bantered with border officials speaking as he gazed upon the wall before he approached a plaque and signed it.

-ABC News' John Parkinson and Ben Gittleson