The response from a few of his fans in Iowa: laughter, sometimes a shrug and the confidence that Mr. Art-of-the-Deal knows exactly what he's doing.
"I think he thinks he has the Iowa caucus in the bag. That's why he's skipping it," said Don Leigh, a meat manager at a grocery store who lives in Iowa City and attended Trump's rally at the University of Iowa on Tuesday night. Leigh plans to caucus for Trump on Monday and said, at this point, there's little that could sway him to vote for someone else — but, he added, he likes watching Trump debate and will miss seeing him on Thursday.
Twitter filled with calls for Trump's supporters to boycott the debate, along with praise for Trump's plan to host an event that would compete with the debate and raise money for programs that support military veterans, especially those who were injured at war.
The account @HispanicsTrump tweeted: "Instead of sitting in a circle and arguing with other candidates Trump is going to raise money for vets. True leadership. #BoycottDebate." Fans circulated a photo of Trump flashing a thumbs-up with this message: "Guess who already won the Fox News debate?" Several of Trump's staffers and volunteers retweeted a video compilation of the times Fox News's Megyn Kelly — one of the debate moderators for Thursday night — has reported critically on Trump.
As Trump toyed with the idea of skipping the debate early Tuesday afternoon, he posted a poll on Twitter asking: "Should I do the #GOPdebate?" Followers could vote yes or no, and around 8 p.m. Tuesday, nearly 90,000 people had voted — and 76 percent told him "yes," he should do the debate. Two hours later, nearly 130,000 had voted, and "yes" still was in the lead, although by a lower 60 percent. Wednesday morning, "yes" was still in the lead with 57 percent of nearly 150,000 votes.
But supporters can like watching Trump debate while still supporting his decision to not show up. As Trump debated this question, Twitter filled with criticisms — often nasty ones — of Kelly. Trump also posted a video on Instagram Tuesday afternoon showing him sitting behind his desk and saying: "Megyn Kelly's really biased against me. She knows that, I know that, everybody knows that. Do you really think she can be fair at a debate?"
Matt Tyda, who lives in Marshalltown, Iowa, and attended a Trump rally there on Tuesday evening, said Trump’s decision “means nothing to me," and that Fox News has been unfair in its coverage. He cited the network's recent reporting, which appeared to mock Republican Sen. Rand Paul, as an example of its poor coverage.
"The media, you can’t believe anything, especially anything Fox News says, wants or does," Tyda said. "Fox News is a joke."
Not everyone thought it was a smart move, and there was some disbelief at the rally in Marshalltown.
“I’ve watched the debates, and I’m sorry, but Fox has done a terrific job with the debates. I’m surprised,” said Marcia Ziel, a retiree from Marshalltown. Trump's decision is likely to disappoint many Iowans, she added, but “I don’t think it’ll change their vote, but it would be very disappointing.”
Karen Farmer, a retiree from Cedar Rapids, said she expects Trump will change his mind.
"I would think that he would show up in the debate, and I think he will,” she said. “He’ll be there.”
At Trump's Iowa City rally later in the evening, retirees Jan and John Kardos said they have watched nearly all of the debates — missing the one on Fox Business, a channel they couldn't find — and like how Trump keeps things unpredictable and exciting. When asked if the debate will be different without Trump on the stage, they burst out laughing.
"Of course! No question about it, no question about it," Jan Kardos said.
John Kardos added: "He livens things up a lot. One of the reasons I came here was for entertainment."
The couple agreed with Trump's decision to not participate.
"I respect a strong stand — it doesn't take anything away from him, I don't think," said Jan Kardos, who lives in Iowa City and is still trying to make up her mind on whom to caucus for. Although Ohio Gov. John Kasich (R) is a favorite, Trump is an option for her.
"He's making a point," said John Kardos, who also hasn't made up his mind, but likes New Jersey Gov. Chris Christie. "And he probably doesn't need the exposure."
Ed O'Keefe contributed to this report from Marshalltown, Iowa.