The Republican party descended into full-scale civil war on Thursday, with its last presidential nominee, Mitt Romney, launching withering attacks against current front-runner Donald Trump, who responded with fury.

“Let me put it plainly, if we Republicans choose Donald Trump as our nominee, the prospects for a safe and prosperous future are greatly diminished,” Romney said in an extraordinary broadside, delivered in Salt Lake City, Utah, designed to halt Trump's march to the nomination.

Romney, the chairman of Lexington, Massachusetts-based Solamere Capital, described Trump as vulgar, sexually debased, and out of step with America. “Dishonesty is Donald Trump's hallmark,” he said.

Hours later, at a campaign rally in Maine, Trump blasted Romney with his own flurry of insults, calling him a "failed candidate" who "let us down" after running a "horrible campaign," and also recalled meeting with the former Massachusetts governor during the 2012 campaign when Romney sought and received his endorsement. 

“I could’ve said, 'Mitt, drop to your knees,' he would have dropped to his knees," Trump said, adding that, "If somebody hits me, I'm going to hit them back harder." 

The spectacle of the party's former standard-bearer and the man who hopes to fill that role trading insults was unlike anything in recent memory in American politics, and sent Republicans scrambling to choose sides in the skirmish. 

Senator John McCain, who battled Romney to win the party's 2008 nomination, wrote on Twitter after Romney's speech that he shared the same concerns. “Hope American ppl think hard about who they want as commander-in-chief,” McCain wrote.

McCain's running mate, Sarah Palin, defended Trump and said he shouldn't “take the bait.” “It's not about you,” she wrote to Trump in a Facebook message. “It's about us. And we've got your back.”

 

Stern warning

Calling Trump a bully who was motivated by greed, Romney asked voters to imagine their children and grandchildren acting like the outspoken former TV reality show host. Romney tore into his party's front-runner, saying Trump's plan to let Russia lead the fight against the Islamic State was “the most ridiculous and dangerous idea of the entire campaign season,” and urged voters to back any other candidate they believed had the best chance of beating the New York businessman.

“His imagination must not be married to real power,” Romney said. “If Donald Trump's plans were ever implemented, the country would sink into a prolonged recession.”

While Trump did not respond to Romney's criticism of his foreign policy proposals, he zeroed in on the former Massachusetts governor's insistence that a Trump presidency would prove disastrous for international trade and throw the U.S. economy into recession.

"When Mitt made the statement, 'he will ruin free trade'— ruin free trade? If I'm losing $505 billion with China, if I'm losing $58 billion a year with Mexico in terms of deficits, what do I want that kind of trade for anyway?" Trump asked rhetorically. "Who needs that kind of trade?"

Trump also sought to cast doubt on Romney's fitness for the White House as some Republicans wonder if he may enter the race and challenge the front-runner. "He doesn't have what it takes to be president," Trump said.

Romney said he was not announcing his own candidacy and would not make an endorsement of any single candidate. Instead, he named all three of Trump's remaining rivals: Florida Senator Marco Rubio, Texas Senator Ted Cruz, and Ohio Governor John Kasich. “One of these men should be our nominee,” Romney said.

 

Party in crisis

The back-and-forth exchange was a spectacle of the Republican Party's identity crisis, playing out in full view of the public. Trump can rightly say that his unorthodox candidacy has brought new voters to the polls for the Republican primaries, voters attracted to his tough talk and promise to “make America great again.” And it's an open question whether Romney is the best messenger to take down Trump.

For one, Romney, a founder of Bain Capital, is viewed—and views himself—as a protector of a Republican establishment that many of Trump's voters would say has lost touch with their day-to-day concerns. Romney's own run against President Barack Obama in 2012 never really came close to unseating the president, in part because Romney was easily painted as a wealthy elitist who benefited from Wall Street ways—the very thing voters in both parties are rebelling against this year.

Also threatening to undermine his message: Romney publicly praised Trump in 2012 while seeking, and winning, the endorsement from the New York businessman. Romney did not mention the endorsement in his speech.

But it was Romney's refusal to back one of the other rivals that partly explains why Trump has been so successful. With support from the party's traditional, pro-business wing splintered between several candidates for most of the past year, Trump quickly assumed front-runner status by winning support from a small plurality in the polls. The constant bickering within the establishment let Trump largely avoid any early, significant attacks, and his strength has only grown: He's won 46 percent of the delegates in the first 15 states that have held nominating contests.

House Speaker Paul Ryan, who was Romney's running mate four years ago, said he wasn’t “going to get into who endorsed who in 2012. If you’re the nominee of the party you want everybody’s endorsement. That’s just how it works.”

“Mitt’s one of our leaders, he’s a principled conservative,” Ryan said on Fox News. “He’s worried about the future of our party.”

Romney's speech at the University of Utah comes as many in the party fear that Trump can essentially end the contest if he pulls out victories in Ohio and Florida, two large, battleground states that hold primaries on March 15.

As the party's 2012 nominee, Romney is the most significant figure in a rapidly intensifying effort by the Republican establishment to take down Trump. His criticism marks the bluntest attempt so far by the Republican establishment to slow Trump’s momentum after his victories on Tuesday, the single biggest day of voting in the Republican race.

Romney offered a litany of reasons why Trump would be bad for the country: Trump's tariffs would touch off a trade war and kill export jobs; his tax plan would balloon the deficit and national debt; his plans overall “would be very bad for American workers and for American families.

“After all, this is an individual who mocked a disabled reporter, who attributed a reporter's questions to her menstrual cycle, who mocked a brilliant rival who happened to be a woman due to her appearance, who bragged about his marital affairs, and who laces his public speeches with vulgarity,” Romney said.

“There is dark irony in his boasts of his sexual exploits during the Vietnam War while John McCain, whom he has mocked, was imprisoned and tortured.”

 

Eager audience

Romney's speech was delivered on a crisp, overcast morning, with snow-covered peaks as a backdrop. Hundreds of students and community leaders lined up two-and-a-half hours early to see the former Massachusetts governor, and packed a 680-chair music hall.

Many in the line that snaked around buildings on the austere campus were registered Republicans who expressed disgust with Trump's raw rhetoric and his lack of foreign policy experience.

“One of the most disgusting things to me is his refusal to denounce the KKK,” said Nick Clayson, 21, a political science student at Utah State University and registered Republican. “That's a huge issue for me. If it came down to Clinton or Trump I would want a third party candidate to enter the race.”

“Trump tells it like it is, he's not politically correct—he says what people want to hear and doesn't hold anything back,” said John Greene, 47, who owns a real estate business in Salt Lake City. “With his lack of foreign policy experience he could run this country into the ground.”

Others in the queue flew in from out of town the night before and were undecided about who they would support in their state's upcoming primary election.

“I came to see if he can change the tide,” said Rachel Walston, a financial adviser from North Carolina and registered Republican who turns 37 today. “For the first time in my life I might vote for a Democrat if it comes down to Trump.”

Several pointed to a groundswell of support in Salt Lake City, the home of the Mormon church, for Romney to enter the race. The Bain Capital founder is a favorite son in Utah—a prominent Mormon who gained fame after he turned a scandal-plagued 2002 Winter Olympics into a profitable venture.

“I wish Romney would run,” said Don Gilbert, 77, a retired loan manager who has lived his entire life in Salt Lake City. “As far as honesty and dealing with people and he's had good experience in government. Trump is a little scary.”

Many agreed, however, that if forced to choose between Trump and former Secretary of State Hillary Clinton, they would hold their nose and vote for the former reality TV star.

“If it came down to it I would probably vote for Trump,” said Josh Brewer, 34, a business management major at Utah Valley University. “I have to make my vote count.”

—With assistance from Toluse Olorunnipa and Jonathan Stearns.

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