Former Vice President Mike Pence announced his presidential campaign in Iowa on Wednesday with a repudiation of Donald J. Trump, portraying his former boss — and now rival — as unfit for the presidency and going further than ever before in condemning the character and values of the man he loyally served for four years.
Before a crowd of several hundred on the campus of the Des Moines Area Community College, Mr. Pence focused on something that many in his party have tried to desperately avoid: Mr. Trump’s actions on Jan. 6, 2021.
“Jan. 6 was a tragic day in the life of our nation,” Mr. Pence said. “But thanks to the courage of law enforcement, the violence was quelled, we reconvened the Congress. The very same day, President Trump’s reckless words endangered my family and everyone at the Capitol.”
He added: “But the American people deserve to know on that fateful day, President Trump also demanded I choose between him and our Constitution. Now voters will be faced with the same choice. I chose the Constitution, and I always will.”
No other major Republican candidate for president has even mentioned the attack on the Capitol in an announcement speech. Most elected Republicans have contorted themselves to avoid ever talking about that day — believing it only alienates their voters. A growing number of Republicans are going even further, trying to falsely reframe the attack on the Capitol as an inside job by the F.B.I. or by leftist groups pretending to be Trump supporters.
Instead, Mr. Pence described his own actions that day in certifying Joseph R. Biden Jr.’s victory as a decisive moment that proved his mettle, and Mr. Trump’s actions that day as disqualifying.
“The Republican Party must be the party of the Constitution of the United States,” Mr. Pence said to applause.
“Anyone who puts themselves over the Constitution should never be president of the United States,” he said. “ And anyone who asks someone else to put them over the Constitution should never be president again.”
Mr. Pence’s use of the word “never” took him across a line he had not breached until now, even as he has criticized Mr. Trump since Jan. 6. His announcement speech put him closer to more outspoken Republicans such as former Representative Liz Cheney, who have described Mr. Trump as morally unfit to occupy the Oval Office.
With his remarks, Mr. Pence raised an immediate question for his campaign: As a criteria for participating in the G.O.P. primary debates, the Republican National Committee requires each candidate to sign a pledge that they will support the party’s eventual nominee.
Mr. Pence has put himself in the potential position of having to support a candidate in Mr. Trump, the front-runner in the Republican Party, who he said should “never” be president.
Despite that, only minutes after his speech, Mr. Pence promised in an interview with Fox News that he would support the Republican nominee for president, “especially if it’s me.”
The former vice president addressed a thorny issue of his long-shot candidacy: how to account for his years of supporting a candidate whose character and positions were well known in 2016, and whose presidency was consistent with some of those expectations. In Mr. Pence’s telling, the Mr. Trump with whom he shared a ticket has, in fact, changed.
Mr. Pence homed in on three issues to draw an ideological contrast with Mr. Trump: abortion, fiscal conservatism and foreign policy.
“When Donald Trump ran for president in 2016, he promised to govern as a conservative. And together we did just that,” Mr. Pence said, leaving unmentioned the inconvenient fact that the Trump-Pence administration added around $8 trillion to the national debt.
“Today he makes no such promise,” he added. “After leading the most pro-life administration in American history, Donald Trump and others in this race are retreating from the cause of the unborn.”
While Mr. Pence went after Mr. Trump in his speech, he used an announcement video earlier in the day to attack President Biden. “Our country’s in a lot of trouble,” Mr. Pence said in his nearly three-minute-long announcement video, accusing Mr. Biden and the “radical left” of weakening America “at home and abroad.”
Citing “runaway inflation,” a looming recession, a southern border “under siege,” unchecked “enemies of freedom” in Russia, China “on the march,” and what he calls an unprecedented assault on “timeless American values,” he promised to deliver what he said the nation sorely needed.
“We’re better than this,” Mr. Pence says. “We can turn this country around. But different times call for different leadership. Today our party and our country need a leader that’ll appeal, as Lincoln said, to the better angels of our nature.”
In his speech, Mr. Pence went on to make clear that unlike other Republican candidates he wouldn’t be afraid to cut spending on Social Security and Medicare in order to confront the nation’s debt crisis.
Then he turned to foreign policy. He said Mr. Trump had walked away from America’s traditional role on the world stage. He described the United States as “the leader of the free world” and an “arsenal of democracy.” He criticized Mr. Trump for describing President Vladimir V. Putin of Russia as a “genius” and Gov. Ron DeSantis of Florida for describing Russia’s invasion of Ukraine as a “territorial dispute.”
