The tiff between Donald Trump and Pope Francis on Thursday was the latest example of what's become a persistent theme of Trump's presidential campaign: caustic battles over religion, immigration or sexuality that animate his supporters and capture headlines.

When Trump first began campaigning, his comments baffled political observers, but as his lead in the polls only increased, it has become clear that his backers see his unapologetic, brash style as a strength, no matter whom he goes after.

In no particular order: Trump has called Iowans “dumb” for backing Ben Carson, has complained that any number of television anchors treated him badly and has repeatedly mocked rival candidate Jeb Bush as “low-energy,” a preferred insult of Trump’s.

More gravely, Trump has also labeled Mexicans "rapists" and drug runners; has dismissed the war record of Sen. John McCain (R-Ariz.), who was held captive in Vietnam for several years; and has called to ban Muslims from entering the country.

So what has Trump said exactly?

Iowans

As his poll numbers began to lag in Iowa last fall, he offered choice words for voters in the state, which kicked off primary season Feb. 1.

"How stupid are the people of Iowa?" he said at a local event.

Trump finished second to Texas Sen. Ted Cruz in the state's caucuses.

Jeb Bush

The former Florida governor has become a relentless target for Trump, who calls him "low-energy" on the campaign trail and in debates. Trump has even gone after Bush's family -- in particular, former President George W. Bush, whom he recently blamed for failing to keep America safe from the Sept. 11 attacks.

Funny that Jeb(!) didn't want help from his family in his failed campaign and didn't even want to use his last name.Then mommy, now brother! — Donald J. Trump (@realDonaldTrump) February 15, 2016

Ted Cruz

The Texas senator is Trump's main rival for the party's nomination. In recent weeks, Trump has questioned Cruz's citizenship (he was born in Canada to an American mother and a Cuban father) and has assailed him repeatedly as a "nasty" person who will "lie" to capture the nomination.

Bill and Hillary Clinton

They used to be family friends -- but no longer. Hillary Clinton said Trump had a "penchant for sexism," and after former President Clinton hit the campaign trail on her behalf, Trump pounced.

If Hillary thinks she can unleash her husband, with his terrible record of women abuse, while playing the women's card on me, she's wrong! — Donald J. Trump (@realDonaldTrump) December 28, 2015

Hillary Clinton has announced that she is letting her husband out to campaign but HE'S DEMONSTRATED A PENCHANT FOR SEXISM, so inappropriate! — Donald J. Trump (@realDonaldTrump) December 27, 2015

The media

I hear that dopey political pundit, Lawrence O'Donnell, one of the dumber people on television, is about to lose his show-no ratings?Too bad — Donald J. Trump (@realDonaldTrump) June 25, 2015

Women

After the first Republican presidential debate in August, Trump took aim at Megyn Kelly, the Fox News anchor who co-moderated the gathering. The billionaire businessman felt that her questions about misogynistic comments he'd made in the past were unfair.

"You could see there was blood coming out of her eyes," he said in a CNN interview after the debate. "Blood coming out of her wherever."

Re Megyn Kelly quote: "you could see there was blood coming out of her eyes, blood coming out of her wherever" (NOSE). Just got on w/thought — Donald J. Trump (@realDonaldTrump) August 8, 2015

He also has gone after Carly Fiorina, the former Hewlett-Packard CEO who exited the race after a disappointing showing in New Hampshire, disparaging her appearance.

"Look at that face!" he told a Rolling Stone reporter aboard his private plane when Fiorina appeared on a television screen. "Would anyone vote for that? Can you imagine that, the face of our next president?

Mexicans

During his campaign launch in June, Trump labeled Mexicans "rapists" and drug runners -- statements he has not backed down from.

Muslims

In the wake of the Paris and San Bernardino terrorist attacks, carried out by individuals who indicated they were inspired by Islamic State, Trump called to ban Muslims from entering the United States.

The proposal was condemned by Democrats and Republicans alike.

Donald Trump is unhinged. His "policy" proposals are not serious. — Jeb Bush (@JebBush) December 7, 2015

He defended the proposal and has remained committed to it in an effort, he says, to protect Americans.

Sen. John McCain

In comments at an Iowa forum, he mocked McCain, who spent more than five years as a prisoner in North Vietnam.

“He's a war hero because he was captured. I like people that weren't captured, OK? I hate to tell you. He's a war hero because he was captured, OK? And I believe — perhaps he's a war hero. But right now, he's said some very bad things about a lot of people,” Trump said.

Pundits predicted his campaign would quickly end after he criticized McCain. Not even close.

The disabled

While on the campaign trail, Trump cited a Washington Post article from days after 9/11 to undergird his claim that Muslims in New Jersey celebrated the attacks. But when the reporter, Serge F. Kovaleski, who now works for the New York Times, corrected Trump, he took aim. At a rally he flailed his arms and mocked Kovaleski, who suffers from a chronic condition that limits the movement of his arms.

The pope

Trump took on Pope Francis on Thursday, complaining that the pontiff's criticism of Trump's proposal to build a border wall was "really not very nice." And in typical Trump fashion, he went well beyond explaining how insulted he was, also claiming that Islamic State, or ISIS, wanted to attack the Vatican and warning, middle-school-style, that Francis would be sorry that he ever trusted in politicians other than Trump.

"If and when the Vatican is attacked by ISIS, which as everyone knows is ISIS’s ultimate trophy, I can promise you that the pope would have only wished and prayed that Donald Trump would have been president because this would not have happened," Trump said in his statement. "ISIS would have been eradicated, unlike what is happening now with our all-talk, no-action politicians."

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