Watching the excellent documentary “Ebola in America: Epidemic of Fear” is to relive the confusion and controversies of the summer of 2014: the initial public health mistakes, the divided and unclear responsibilities, the hysterical coverage on cable TV. But it is the political role played by Republicans and conservatives that stands out, and not in a good way.

At every stage, elements of the right made a reasonable, science-based response to Ebola more difficult. Against the advice of the Centers for Disease Control and Prevention (CDC), New Jersey Gov. Chris Christie quarantined a nurse returning from West Africa who had tested negative for the disease. Some conservative media outlets spread false information about the disease to exaggerate an impression of public health incompetence.

But it was Donald Trump who led the opposition. He tweeted: “The U.S. must immediately stop all flights from EBOLA infected countries or the plague will start and spread inside our ‘borders.’ Act fast!” And: “Ebola is much easier to transmit than the CDC and government representatives are admitting.”

Health officials were not lying. Travel to and from West Africa was essential for medical personnel and aid workers to defeat the disease at its point of origin. Trump’s ban would have made Ebola materially more likely to spread beyond control.

President Obama recognized the work and leadership of U.S. health-care workers in their response to the Ebola threat at the White House on Wednesday. (Ashleigh Joplin/AP)

What kind of politics is ascendant in the United States? A distrust of institutions that borders on conspiratorial. Here is Trump again: “Healthy young child goes to doctor, gets pumped with massive shot of many vaccines, doesn’t feel good and changes — AUTISM.” And: “I am being proven right about massive vaccinations — the doctors lied.” And: “So many people who have children with autism have thanked me — amazing response. They know far better than fudged up reports!”

Lying doctors. Fudged reports. It would all be disturbing — if it were not conspiratorial nonsense. No connection has ever been demonstrated between vaccinations and autism. And this particular nonsense is potentially deadly. Trump is undermining a consensus for vaccination that builds up “herd immunity” and saves the lives of children.

Who else is plotting against us — I mean, other than public health officials and your local pediatrician? Well, the Mexican government, because “they send the bad ones over because they don’t want to pay for them.” And how does Trump know the “cunning” Mexicans are purposely exporting criminals? Because some unspecified “Border Patrol people” told him.

Even more disturbingly, there are the “thousands and thousands” of Muslims in New Jersey who Trump claims celebrated the Twin Towers collapsing. For proof of this, he linked to an article at the Infowars website, run by Alex Jones, who has famously argued that the U.S. government was behind the 9/11 attacks. Trump has pledged that, if he is elected, “you will find out who really knocked down the World Trade Center.”

And then there are the black criminals who are responsible, according to a Trump retweet, for 81 percent of homicides against whites. Except that this turned out to be a racist myth from a white supremacist source.

And then there is the death of justice Antonin Scalia. “They say they found a pillow on his face,” responded Trump, “which is a pretty unusual place to find a pillow.”

Republican presidential candidates Ben Carson, Donald Trump and Rand Paul responded to a question about vaccines and autism at the GOP debate. (CNN)

Does Trump really believe that liberals may have ordered a hit on a Supreme Court justice? Who knows? We do know he finds such ideas useful. Trump emerged in conservative circles by questioning Barack Obama’s citizenship, and thus the legality of his presidency. This required the existence of a conspiracy to hide the circumstances of Obama’s birth. “They cannot believe what they’re finding,” he said of “people that have been studying it.” Having actually discovered nothing, Trump doubled down on a deception.

As a leader, Trump has succeeded by appealing to stereotypes and ugly hatreds that most American leaders have struggled to repress and contain. His political universe consists of deceptive experts, of scheming, of criminal Mexicans, of lying politicians and bureaucrats and of disloyal Muslims. Asked to repudiate David Duke and the Ku Klux Klan, Trump hesitated, later claiming a “bad earpiece.” Asked to repudiate the vicious anti-Semitism of some of his followers, Trump responded, “I don’t have a message to the fans.” Wouldn’t want to offend “the fans.”

This is not flirting with the fringes; it is French-kissing them. Every Republican official endorsing Trump should know: This is the company he keeps. This is the company you now keep.

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