It's a good thing Donald Trump thinks he doesn't need a unified Republican Party to win in November.

Judging by his statements on those who refuse to endorse him, he isn't going to get it.

New York Times:

Donald J. Trump said he would not rule out an effort to remove Representative Paul D. Ryan as chairman of the Republican National Convention if he did not endorse Mr. Trump’s candidacy.

Mr. Trump stopped short of calling for Mr. Ryan, the speaker of the House, to step down from his convention role. But in an interview that aired Sunday on NBC’s “Meet the Press,” Mr. Trump said there could be consequences in the event that Mr. Ryan continued withholding his support.

“I will give you a very solid answer, if that happens, about one minute after that happens, O.K.?” Mr. Trump said. “There’s no reason to give it right now, but I’ll be very quick with the answer.”

Mr. Trump has shown little interest over the last few days in placating his critics inside the party, including Mr. Ryan. Mr. Ryan, a representative from Wisconsin, said on Thursday that he was not ready to endorse Mr. Trump, citing reservations about his political style and policy agenda. The two men are scheduled to meet privately in Washington next week.

But on “Meet the Press,” Mr. Trump struck a dismissive tone toward Mr. Ryan and responded with outright hostility to other Republican critics who have refused to back his campaign.

Jeb Bush, he said, was “not honorable” for breaking his promise to endorse the party’s nominee. Mitt Romney, he said, was “ungrateful” for the help Mr. Trump gave him in the 2012 election. Mr. Trump referred to Lindsey Graham, the South Carolina senator who said Friday he would never vote for Mr. Trump, as “this lightweight.”

Of Mr. Ryan, he said: “I’d like to have his support. But if he doesn’t want to support me, that’s fine, and we have to go about it.”

Asked about Mr. Trump’s remarks on the convention, Brendan Buck, a spokesman for Mr. Ryan, replied, “The speaker looks forward to meeting with Mr. Trump on Thursday.”

Other allies of Mr. Trump have gone further in criticizing Mr. Ryan for declining to issue an immediate endorsement.

And Trump has unleashed a key surrogate to assist Ryan's GOP primary opponent, Paul Nehlen, in bringing Ryan down:

On CNN’s “State of the Union,” Palin said Ryan’s announcement that he wasn’t ready to support Trump showed he was “disconnected” and said that he was “soon to be Cantor-ed,” referring to former House Majority Leader Eric Cantor, who was defeated in a stunning 2014 primary in Virginia.

“Paul Ryan and his ilk, their problem is they have become so disconnected from the people they were elected to represent,” said Palin, the GOP’s 2008 vice presidential candidate. “Their problem is they feel so threatened at this point that their power, their prestige, their purse will be adversely affected by this change that is coming with Trump.”

Following Ryan’s announcement last week that he wasn’t ready to support Trump, Nehlen suggested he would back the real-estate mogul ahead of the primary for Wisconsin's 1st Congressional district.

Palin said she “will do whatever I can” to help Nehlen, noting that she hadn’t had a chance yet to call the candidate to inform him of her support.

She also suggested Ryan’s announcement might be motivated by his own presidential ambitions.

“If the GOP were to win now, that wouldn’t bode well for his chances in 2020,” she said. “I think that one is Paul Ryan’s reason.”

I don't think Ryan is going to be around in August to run in that primary.  Unless he does a 180 and comes out in support of the nominee of his party, House Republicans won't let him remain as speaker.  I would put the odds of Ryan resigning after his meeting with Trump this week at 50-50.

There are plenty of GOP congressmen who despise Trump but realize he is the party's nominee and there is no realistic recourse but to support him.

The GOP is slowly becoming Trump's party, and he could probably engineer Ryan's downfall if he wanted to.  I doubt Ryan will stick around to be humiliated by Trump if his position remains the same.