... 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."

... 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. ...