If Pepsi said such hyperbolically bad things about Coke, would anyone believe it?

If Ford devoted its advertising to trashing Chevrolet in such histrionic terms, would that be credible?

Yet somehow voters who otherwise think of themselves as savvy consumers seem completely gullible when it comes to campaign advertising. Why? We are right to worry about Russia trying to interfere in American politics, yet we also ought to be concerned about American political consultants who push whatever psychological buttons they can push to provoke a Pavlovian response from voters.

This kind of emotional manipulation is practiced with equal glee by both parties but the ad in question today comes from the Democratic side —specifically the Latino Victory Fund.

The one-minute video shows a sinister-looking white man chasing down minority kids with his pickup truck that’s adorned with three tell-tale symbols — a Confederate flag, a Tea Party license plate and a bumper sticker for Ed Gillespie, the Republican candidate for governor. At the end, this is all revealed to be a dream, as the kids wake up shaking in the middle of the night, while the narrator intones: “Is this what Donald Trump and Ed Gillespie mean by ‘the American dream’?”

Republicans called the ad a sickening resort to fear-mongering. The campaign of Democrat Ralph Northam distanced itself from the ad produced by an independent group, saying he did not condone the message. The Latino Victory Fund defended the ad, saying “We held a mirror up to the Republican Party, and they don’t like what they see.”

We are not Republicans, but we don’t like what we see, either. We’ll explain why.

First, it’s factually wrong — no small thing. The ad suggests that Gillespie supporters are racist vigilantes who want to run down minority kids. Really? Really??

Secondly, the ad does not target the candidate but rather his supporters. That seems akin to Hillary Clinton’s comment about many supporters of Donald Trump being a “basket of deplorables.” Her comment was misinterpreted; she went on to define those deplorables as people who are “racist, sexist, homophobic, xenophobic — Islamophobic — you name it.” Ideally, even Republicans would agree that racists, sexists and the lot are deplorable, but her comment came off as showing contempt for Trump supporters in general. This ad doesn’t even have that Clintonesque nuance. It just shows a white guy in a pick-up truck — and implies Gillespie supporters want to kill minority kids. Umm, that’s a lot of Virginians right there who are being called not just homicidal but genocidal.

We’ve already said that campaign advertising is exaggerated so we understand we’re not supposed to take this ad literally. But the message is unmistakable — Republicans are bad people. That’s not a good message to be sending in a democracy, where come the day after the election we’re all still going to be living together and working together in a civil society. Perhaps you think Gillespie is wrong on the issues, but that doesn’t make his supporters bad people.

To say this ad holds a “mirror up to the Republican Party” is as dangerous as GOP Senate hopeful Corey Stewart declaring over the weekend that “the Democrats really fall into four basic categories: criminals, communists, crackheads, and weirdos.”

This is not harmless campaign rhetoric. This is language that leads to tyranny. If Republicans really do want to run down kids, why shouldn’t Democrats lock them all up? If Democrats really are “criminals, communists, crackheads and weirdos” why not herd them all into concentration camps? Republicans ought to be denouncing Stewart’s reckless words and Democrats ought to be denouncing the Latino Victory Fund ad. Both spring from the same poisonous well where it’s become acceptable to not just say the other side’s candidate is wrong on the issues, but the other side’s supporters are existential threats to society.

The Latino Victory Fund does have some legitimate issues: The Trump administration’s anti-immigration policies have provoked fear; Trump’s reaction to the white supremacists marching in Charlottesville was both weak and alarming.

If this ad had shown an immigration officer snatching kids off the street, that would have been fair comment. Last week, immigration agents in Texas really did seize a 10-year-old girl from a hospital and set in motion deportation proceedings. That’s factual, and just as horrifying. The girl has lived in the United States — albeit without proper paperwork — since she was an infant. She has no memories of the Mexico that our government wants to send her back to. Is that really the America we want to be, where federal agents are grabbing kids out of surgery and sending them to some strange country? But that’s not what the ad shows.

Most Republicans are basically wrong on immigration. Demographically, the United States needs more young adults to offset a graying population that is counting on somebody to fund their Social Security benefits. Economically, the nation needs a bigger labor pool to drive an economy that is increasingly tilting toward retirees. These, by the way, are not ideological viewpoints; they are the statistical conclusions of a Federal Reserve report last year. (They were also campaign planks of former Florida Gov. Jeb Bush, but you see where that got him.)

Closer to home, the GO Virginia economic development council for Southwest Virginia just produced a report that warned a declining population makes it hard to retain existing businesses in the region, much less attract new ones. Southwest Virginia needs new residents; whether they come from New Jersey or New Delhi is irrelevant. Southwest Virginia needs immigration.

That’s a hard conversation to have, and this ad makes it even harder. Instead of demonizing every middle-aged white guy with a pick-up truck, a rebel flag and a Tea Party license plate, the Latino Victory Fund needs to be making the case for why immigration is actually in that guy’s best interest — if he wants to keep his job and collect his retirement benefits.

Instead, the fund just called him a racist. Don’t be surprised if he doesn’t listen to anything after that.