Editor’s Note: Julian Zelizer is a professor of history and public affairs at Princeton University, a New America fellow and author of “The Fierce Urgency of Now: Lyndon Johnson, Congress, and the Battle for the Great Society.” The opinions expressed in this commentary are his.

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Zelizer: GOP candidates have tried to grab attention with outrageous remarks

He says the only way this kind of politics will ever be checked is if voters object

CNN  — 

Republicans have been saying some rather remarkable things on the campaign trail.

While the Democrats were debating in Las Vegas, Mike Huckabee received attention for his eye-catching tweets. “I trust @BernieSanders with my tax dollars like I trust a North Korean chef with my labrador!” In another tweet he added, “Racism exists because we have a sin problem in America, not a skin problem.”

This is not the first time that one of the Republican candidates has said or written something offensive. In a crowded field of 15 candidates, voters have heard an endless stream of controversial statements.

Before the Democratic debate, it was Ben Carson making headlines, and rising in the polls, with comments to Wolf Blitzer about how German Jews could have protected themselves from the brutal Nazi regime if only they had been able to possess handguns.

In the second Republican debate, Carly Fiorina mischaracterized a video from an anti-abortion group as showing a “fully formed fetus on the table, its heart beating, its legs kicking, while someone says we have to keep it alive to harvest its brain.” It did not.

Donald Trump remains the king of controversy, with blistering statements like his claim that Mexico was sending the U.S. immigrants who were rapists and people who bring drugs and crime. Last week, with a provocative statement certainly designed to get attention, he slammed President George W. Bush by saying that 9/11 happened under his watch. When Bloomberg anchor Stephanie Ruhle retorted it wasn’t fair to blame Bush for the attack, Trump said, “He was president, OK? Blame him or don’t blame him, but he was president. The World Trade Center came down during his watch.”

The outsiders have not been alone. Jeb Bush recently characterized Democrats’ message to African-American voters as being: “Get in line and we’ll take care of you with free stuff.”

The escalation of this kind of polemical rhetoric among Republican candidates has been unsettling to many Americans. We have seen a click-bait primary where Republicans are feeding a media hunger for the most dramatic and shocking. Sensational and provocative is in, for the traditional media and on social media.

The same is becoming true in politics. Snappy one-liners have been commonplace for a while, especially in the era of television campaigns. But in 2015, invective is on the verge of becoming the norm.

The impact of politicians embracing this style can be absolutely devastating to the nation. Shock politics is nothing new. When politicians have used demagogic appeals in the past, they have also whipped up uglier elements of the polity into an uncontrollable frenzy. Because of their positions, they can give legitimacy to dangerous statements.

One of the most famous moments was back in the 1950s and 1960s when Southern politicians like Alabama Gov. George Wallace, also a presidential candidate, riled up Southern and Northern whites by warning that civil rights activists posed a danger to democracy. An effect was to stoke the flames behind the violent encounters where whites clashed with peaceful demonstrators who were seeking equality before the law.

In 2008, vice presidential candidate Sarah Palin appealed to some of the most right-wing elements of the Republican base, fostering doubts about the patriotism of Democratic candidate Barack Obama. “Our opponent though, is someone who sees America it seems as being so imperfect that he’s palling around with terrorists who would target their own country.”

During one town hall meeting, the Republican nominee, John McCain, was taken aback by the kinds of statements he was hearing. As he spoke to an audience yelling out things like “liar” and “terrorist” in reference to Obama, McCain grabbed the microphone from one woman who said that “Obama is an Arab.” The Republican nominee said angrily, “No, ma’am. He’s a decent family man and citizen that I just happen to have disagreements with on fundamental issues.”

It was no surprise that McCain recently warned that Trump had “fired up the crazies.” Palin never stopped. In 2009, Palin was one of the first mainstream figures alleging that there were legitimate questions about Obama’s citizenship.

Politicians are also a class of people who like someone else to test the waters, and once they see something works or – equally important – does not do harm, they will mimic what’s been done.

In a competitive environment like the one Republicans face, this creates incentive to emulate the worst in the pack. There have been other moments when we have seen this kind of race to the bottom. In the late 1910s and early 1920s, for instance, politicians in both parties espoused harsh, nativist sentiment about immigrants that eventually produced draconian restrictions preventing anyone entering from Eastern Europe.

During the late 1940s and early 1950s, Sen. Joseph McCarthy of Wisconsin unleashed a fierce assault on opponents, charging them with being communists. In an age when this meant treason, such accusations could – and did – destroy lives. It took the Boston lawyer Joseph Welch, during the Army-McCarthy hearings in 1954, to ask, “Have you no sense of decency, sir?” Welch, representing the Army, the senator’s most recent target, was livid when McCarthy publicly accused one of his staff of being a communist. McCarthy would eventually be discredited, but the kind of anti-communist attacks that he helped to perfect would continue into the next few decades.

While nasty campaign statements are as American as apple pie, the speed of the current media environment makes this kind of political strategy even more dangerous, since there is almost no time to push back. When someone like Huckabee or Carson unleashes one of these blasts, they instantly go viral. The time that it takes statements to hit what was once called the front pages is now virtually zero.

The flow of information is constant. Editorial and production barriers are much lower than ever before, especially since candidates can easily reach national audiences through Facebook, Twitter and other social platforms, without even having to go through the news media. So when a candidate makes outlandish claims, his or her words spread at a breathtaking speed. Even when there is follow-up and opponenets ask questions, the response is usually too late to get careful evaluations of statements into the public sphere before some people have formed their impressions.

Fortunately, in this primary season Democratic candidates have not succumbed to the click-bait culture, though temptations remain strong.

The only way this kind of politics will ever be checked – particularly in the age of the Internet – will be as a result of voters themselves deciding to express their disapproval, through the polls and through the ballot box, telling politicians that anything does not go. The public needs to start asking if some of these candidates have any sense of decency anymore.

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