Donald Trump said he chose his running mate to inspire party unity. The goal of his presidential convention was party unity. But the New York billionaire isn’t any closer to uniting the party because of the man who got the second most votes in the primary: Ted Cruz.

Republicans spent much of the past year scheming behind closed doors, searching for ways to shut down Trump’s presidential campaign. On Wednesday, that conflict spilled out into the Quicken Loans Arena courtesy of the Texas senator – and Trump knew it was coming.

On the third night of Trump’s four-day presidential convention – headlined by Indiana Gov. Mike Pence, the party’s vice presidential nominee – the senator from Texas stole the show by refusing to endorse his one-time rival. After Trump’s campaign chairman dominated headlines on Monday for railing against Ohio Gov. John Kasich, Cruz’s move all but assured a pitched battle in the media carrying through Thursday and into the climactic night and the biggest speech of Trump’s political career.

“We’re writing his political obituary – he’s dead,” Stephen Bannon, executive chairman of Breitbart News, the influential right-wing website that was an early fan of Cruz, said about the Texas senator.

One of the most emotional moments of the convention so far began with 20,000 loyalists greeting Cruz with thunderous applause and ended with thunderous boos as it became clear a succinct endorsement wasn’t coming.

“A big middle finger to this entire convention,” said Shaun Ireland, a Texas delegate, just minutes later on the convention floor. “This is the worst possible thing he could have done.”

Cruz, infamous in the Senate for looking out only for himself, proved again that he was willing to go it alone as the party rallied around Trump during an evening of speeches from Republican heavyweights and some of its most ambitious politicians.

“Wow, Ted Cruz got booed off the stage, didn’t honor the pledge! I saw his speech two hours early but let him speak anyway. No big deal!” Trump said late Wednesday on Twitter.

Earlier in the day, his campaign chairman Paul Manafort said he would be personally viewing the Cruz speech in advance. “I’m comfortable that Senator Cruz is going to talk about his vision for America,” Manafort said. “He’ll give a sign of where he is on Donald Trump that will be pleasing to the Trump campaign and to Republicans.”

Cruz told Trump two days ago he wouldn’t be endorsing him tonight, and that the Trump folks knew what to expect in his speech, according to Cruz strategist Jason Johnson.

In many ways, it was a perfectly symbolic moment in an increasingly chaotic and disorderly convention.

With just one day left in the convention and the biggest speech of all still remaining, the discord within the party and disagreement over why to back Trump has been a consistent theme.

On Wednesday, leading Republicans filling out the primetime lineup sent mixed messages to delegates and television viewers alike.

Some, like Wisconsin Gov. Scott Walker, made an impassioned case to vote for Trump. Others, such as Florida Sen. Marco Rubio, mostly urged America to vote against likely Democratic presidential nominee Hillary Clinton.

Cruz took a third path: voters should at least show up to support the Republicans farther down the ballot.

“Don’t stay home in November,” Cruz said. “Stand and speak and vote your conscience – vote for candidates up and down the ticket who you trust to defend our freedom and to be faithful to the Constitution.”

As the crowd quickly turned on him, the first-term senator could only muster a pained smile as he left the stage. Security escorted his wife, Heidi, out of the arena after the speech, CNN reported.

Cruz’s speech seemed to amount to a political bet that Trump will lose the election, and opting not to throw his lot in with the nominee will preserve his fortunes in 2020. Unclear is whether the gambit will backfire on the Texan by prompting Republicans to blame him for refusing to get in line and help unite the party when it mattered most.

Less than a year ago, Trump and Cruz-then rivals for their party’s presidential nomination – campaigned together in Washington D.C., jointly attacking President Barack Obama’s nuclear deal with Iran.

But as Cruz became Trump’s last real threat in the presidential primary, the political friendship turned bitter and caustic. Trump repeatedly and mercilessly called Cruz a liar. Cruz returned fire, saying Trump was “utterly amoral,” “a serial philanderer,” and “a narcissist at a level I don’t think this country’s ever seen.” He predicted a “disaster” if Trump became the party’s nominee.

The problem for Trump wasn’t just the lack of an endorsement from Cruz, which raised questions about why Trump-who has campaigned on his extraordinary negotiating skills – allowed Cruz to take stage.

It fell to Gingrich, who Trump considered naming as his running mate, to try to disarm the tension in the crowd.

Gingrich, a Georgia Republican, followed Cruz on stage and argued to his audience that they “misunderstood” the senator, who already may be positioning himself for the 2020 presidential race.

“Ted Cruz said you can vote your conscience, for anyone who would uphold the Constitution,” Gingrich said. “In this election, there is only one candidate who would uphold the Constitution.

“So, to paraphrase Ted Cruz, if you want to protect the Constitution of the United States,” Gingrich continued, “the only possible candidate this fall is Trump.”

(c) 2016, Bloomberg · Michael C. Bender