Donald Trump is the presumptive Republican nominee for president. Let that sink in.

One year ago, in May 2015, the nation's political attention was focused on former Florida Gov. Jeb Bush (R), who was making the case for immigration reform, including a path to legal status for undocumented residents. At the time, Bush's message seemed in tune with a new direction for his party. In 2012, the Republican National Committee published a report on how to win the White House in 2016. Key to the plan was expanding the GOP's appeal to minorities, women and young people.

That's not exactly what happened.

As a candidate, Trump has encouraged his supporters to beat up members of the Black Lives Matter movement who protest his rallies, calling them "outside agitators," the term used 50 years ago to describe civil rights activists in the Deep South.

"I love the old days," Trump said in February. "You know what they used to do to [protesters] like that when they were in a place like this? They’d be carried out on a stretcher."

Trump also uses social media to share racist messages with his more than 6 million followers. He tweeted this wildly inaccurate fake crime statistic in November 2015.

Donald Trump

But Trump's open racism should come as no surprise. Many people learn how to approach the world from their parents. Trump's father, Fred Trump, was arrested at a Ku Klux Klan rally in 1927. None other than the great political songwriter Woody Guthrie singled Fred Trump out as a vicious racist. In the 1970s, Trump and his father were sued by the Justice Department for systematically refusing to rent their apartments to black tenants. A decade later, Trump took out full-page ads calling for the execution of five young black men who were accused -- falsely, it turned out -- of raping and savagely beating a jogger in Central Park.

Trump's racially tinged presidential campaign is part of a continuum that goes back to the 1980s and a refinement of the Southern strategy, a political plan devised by former Reagan campaign guru Lee Atwater and former Nixon aide Roger Stone, according to Trump biographer Wayne Barrett.

"The Southern strategy was, 'Let's make the Democrats the black party and the Republicans the white party,'" Barrett said in an interview. "Trump was very close to the Reagan people."

Harry Naltchayan/The Washington Post via Getty Images Donald Trump's convention adviser, Paul Manafort, his longtime adviser Roger Stone, and Reagan aide Lee Atwater all started their careers in the Reagan political operation.

Trump's racism has expanded in recent years. These days, Trump targets Hispanic people, Arabs and Muslims, Native American tribes and Chinese companies with the same menacing, exclusionary language he once reserved for blacks.

Trump's campaign took off last summer, when he claimed that Mexico was sending "crime" and "rapists" to the U.S. Only a "wall" could stop the onslaught, Trump said. Shortly after that, two Trump supporters in Boston beat up a homeless man who looked Hispanic. Trump said his supporters are sometimes "passionate."

Trump's proposed wall is also meant to keep out Muslims, part of his call for a blanket ban on Muslims entering the U.S. There are more than 1.6 billion Muslims in the world, of all races and nationalities. Trump would ban them all.

"I think Islam hates us," the billionaire told CNN's Anderson Cooper in March. "And we can't allow people coming into this country who have this hatred of the United States."

To bolster his case, Trump repeats debunked conspiracy theories and claims -- falsely -- that "thousand and thousands" of Muslims in New Jersey cheered the 9/11 attacks.

The fervor of Trump's hatred for Muslims has real-world consequences. Last month, a woman who allegedly identified herself as a Trump supporter assaulted a Muslim woman outside a Washington, D.C., cafe. According to the victim, the assailant said: "F-ing Muslim. Trash, worthless piece of Muslim trash... I’m going to vote for [Trump] so he can send all of you all back to where you came from.”

Long before Trump painted Muslims and Hispanics as the invading enemy, he attacked Native American tribes, whose casinos might compete with his own. In 2000, Trump took out newspaper ads that claimed the Mohawk tribe in New York had "a record of drug trafficking, money laundering, smuggling illegal immigrants in the United States and violence."

Fifteen years later, Trump would use the same accusations to stoke fear of Hispanics among Republican voters.

"What he's doing now is using racism as the clear underpinning of his campaign and his successful bid for the nomination," said Barrett, author of Trump: The Greatest Show on Earth: The Deals, the Downfall, the Reinvention.

"If the Republicans, and Trump, have any chance of success, it's by exploiting people's fears about the brown people," Barrett said.

Sadly, the overwhelming amount of violent crime in our major cities is committed by blacks and hispanics-a tough subject-must be discussed. — Donald J. Trump (@realDonaldTrump) June 5, 2013

The same combination of fear and meanness that characterizes Trump's racism extends to his sexism.

"You have to treat 'em like shit," Trump once said of women. As a presidential candidate, he's lived up to this motto, insulting rival Carly Fiorina for her "face," making a gross bathroom joke about Fox journalist Megyn Kelly, and posting photos of his wife, a former model, alongside photos of rival Sen. Ted Cruz's wife, a former national security adviser.

Long before he ran for president, Trump made a habit of portraying women as predators, gold diggers and sluts. “I have seen women manipulate men with just a twitch of their eye -- or perhaps another body part," Trump wrote in his best-selling 1987 book The Art of the Deal.

Married three times, Trump's unwanted sexual advances on women have been the subject of lawsuits. His ex-wife, Ivana Trump, used the word "rape" to describe how she felt after a particularly rough encounter with her then-husband.

On the subject of rape, Trump has a record of laying blame squarely on the victim.

26,000 unreported sexual assults in the military-only 238 convictions. What did these geniuses expect when they put men & women together? — Donald J. Trump (@realDonaldTrump) May 7, 2013

Earlier this year, when Trump's presidential campaign manager grabbed and bruised a reporter, Trump accused the woman of being "delusional," and asked, "How do you know those bruises weren't there before?"

Trump's strategy of attacking the victim extends to legal proceedings, including multiple lawsuits against him alleging fraud and racketeering involving Trump University, the for-profit real estate school he created. “I can turn anyone into a successful real estate investor, including you," Trump said in a promotional brochure.

But that's not what happened to the more than 5,000 individuals who are plaintiffs in a class-action lawsuit against Trump and Trump University in California, alleging fraud and false advertising. In New York, Attorney General Eric Schneiderman is suing the now-shuttered Trump U for alleged fraud. Either of these suits could land Trump in open court as a witness as early as this summer.

Trump, like many business titans, is no stranger to the inside of a courtroom. Trump and his companies have settled allegations of hiring discrimination, violating laws that protect returning military veterans, stealing competitors' secrets, defrauding property owners and investors, making false claims about their success, breaking contracts, collusion and negligence.

Still, Trump claims that he never settles lawsuits, and as a candidate, he likes to compare his defense against fraud charges to America's national defense. "The United States should fight back also,” he said recently in a video about the Trump University suits. “We shouldn’t just be settlers, we should fight back. And do what’s right."

To that end, Trump has said he could use the same strong-arm tactics he employs in landlord-tenant disputes to bend other nations to his will.

Topping his list of adversarial countries, after Mexico, is China, which Trump portrays as a crafty thief and a thug, stealing jobs from America's manufacturing sector. "We can't continue to allow China to rape our country, and that's what they're doing," Trump said during a rally last week in Indiana.

Elsewhere in Asia, Trump wants to provide nuclear weapons to Japan and South Korea to counter the threat of the North Korean hermit kingdom. To do so would effectively set off a nuclear arms race in Asia, not to mention that it would violate the Nuclear Nonproliferation Treaty.

Trump also has other ideas that would violate international treaties and laws. He would order soldiers to kill the families of those involved in terror plots, even if their relatives had nothing to do with the crimes.

He's an avid supporter of torture, which he said is an effective tool in the fight against terrorism. “Only a stupid person would say it doesn’t work,” he said of waterboarding in late 2015. Even “if it doesn’t work, they deserve it anyway for what they’re doing to us.” A few months later, Trump told a crowd in New Hampshire, "I would bring back waterboarding. And I'd bring back a hell of a lot worse than waterboarding."

One person who knows about a hell of a lot worse than waterboarding is Sen. John McCain (R-Ariz.), the 2008 Republican presidential nominee. The son of a Naval officer, McCain was captured while serving in Vietnam. He refused an offer of early release as part of a prisoner swap, and was imprisoned and tortured for more than five years.

In January, Trump was asked if he believed that McCain was a war hero. “He’s not a war hero," Trump scoffed. “He’s a war hero because he was captured. I like people that weren’t captured."

Whether American soldiers would obey orders from a Commander In Chief Trump is another story. Top national security officers said point-blank that U.S. forces wouldn't follow an illegal order. But Trump doesn't seem to care. “They won’t refuse," he said in February. "They’re not gonna refuse me. Believe me. I’m a leader, I’ve always been a leader. I’ve never had any problem leading people. If I say do it, they’re going to do it.”

And with Trump, that's the danger -- that anyone, let alone a grand old party, would do what he says.

Speaking to a crowd in January, Trump said his popularity with voters was so rock solid that not even murder could sway his supporters to turn from him. "I could stand in the middle of Fifth Avenue and shoot people and I wouldn't lose voters," he said.

He may be right.

CORRECTION: This article previously misstated that an assault took place in Washington, D.C., last week in a coffee shop. It occurred two weeks ago and outside the shop.

Editor's note: Donald Trump regularly incites political violence and is a serial liar, rampant xenophobe, racist, misogynist and birther who has repeatedly pledged to ban all Muslims -- 1.6 billion members of an entire religion -- from entering the U.S.