It’s become normal for Americans to demand—and receive-a professional assessment of the physical health of the candidates for president—just as they expect updates on the medical state of the president himself. After all, there have been many infamous cases of presidents, from Franklin Roosevelt to Jack Kennedy, who secretly endured serious debilitating illnesses.

Thus, the current crop of presidential hopefuls has provided medical information—though not necessarily from the most objective sources. Hillary Clinton’s doctor, for instance, declared her “fit to serve as president”. Donald Trump’s physician, opined that Trump’s blood pressure and lab results were “astonishingly excellent”, his “physical strength and stamina are extraordinary.” He concluded, “If elected, Mr. Trump, I can state unequivocally, will be the healthiest individual ever elected to the presidency.”

But what about Trump’s mental health?

Surely, we care if a candidate is mentally deranged. If we consider it reasonable that someone with severe psychiatric problems be prevented from purchasing a firearm, why go along with a system that might permit a similarly disturbed individual to gain control over the largest military arsenal the world has ever known?

Indeed, the power of an American president to declare war, to secretly dispatch special forces units to all corners of the globe, to okay the execution by drone or killer teams of anyone he deems a threat to the United States, that power has dangerously escalated over the past few years under Barrack Obama as Congress has refused to even debate Obama’s military actions abroad.

It’s O.K., we’re reassured: you can trust Obama. But what if he we were replaced by someone with a serious character disorder?

Such as, arguably, Donald Trump?

What character disorder? Recent articles from Vanity Fair to Time to Psychology today suggest that Trump is a textbook study of Narcissism. He’s a swaggering egotist; vain, self-centered, convinced of his own greatness, who (some theorize) unconsciously compensates for an underlying low self-esteem with bullying, blustering and braggadocchio.

    

“He’s so classic that I’m archiving video clips of him to use in workshops because there’s no better example of his characteristics,” clinical psychologist George Simon, who conducts lectures and seminars on manipulative behavior recently told Vanity Fair. “Otherwise, I would have had to hire actors and write vignettes. He’s like a dream come true.”

On the other hand, some of the world’s greatest political and business leaders have also been labeled narcissists, from Winston Churchill and Charles de Gaulle, to Bill Clinton, Steve Jobs, Larry Ellison, Elon Musk, and George Soros. Though difficult to live and work with, they’ve proved extremely valuable and productive members of society. We wouldn’t want to be without them.

But, as the Harvard Business Review recently wrote, “The danger is that narcissism can turn unproductive when, lacking self-knowledge and restraining anchors, narcissists become unrealistic dreamers. They nurture grand schemes and harbor the illusion that only circumstances or enemies block their success…

Given the large number of narcissists at the helm of corporations today, the challenge facing organizations is to ensure that such leaders do not self-destruct or lead the company to disaster.”

“…the very adulation that the narcissist demands can have a corrosive effect. As he expands, he listens even less to words of caution and advice….The result is sometimes flagrant risk taking that can lead to catastrophe.”

Dr. George Simon, an expert on personality disorders, explains, “Narcissism becomes particularly “malignant” (i.e. malevolent, dangerous, harmful, incurable) when it goes beyond mere vanity and excessive self-focus. Malignant narcissists not only see themselves as superior to others but believe in their superiority to the degree that they view others as relatively worthless, expendable, and justifiably exploitable.

“This type of narcissism is a defining characteristic of psychopathy/sociopathy and is rooted in an individual’s deficient capacity for empathy. It’s almost impossible for a person with such shallow feelings and such haughtiness to really care about others or to form a conscience with any of the qualities we typically associate with a humane attitude, which is why most researchers and thinkers on the topic of psychopathy think of psychopaths as individuals without a conscience altogether.”

Extreme narcissists, we are told, lash out brutally at those who would dare question their talent or goals. They lie, cheat, change their story from one moment to the next; ignore anything that might challenge their view of the world or of themselves.

According to a recent cover story in Time about Donald Trump and Narcissism, “Trump indeed appears to be emotionally incontinent, a man wholly without—you should pardon the expression—any psychic sphincter. The boundary most people draw between thought and speech, between emotion and action, does not appear to exist for Trump. He says what he wants to say, insults whom he wants to insult, and never, ever considers apology or retreat.”

“Make no mistake,” warns Dr. Simon, “no one is more dangerous than a person who sets him or herself above others to the point that he or she feels entitled to prey on those viewed as inferior

So, bottom line, in light of such warnings about how the dangers of malignant narcissists, after following the outrageous actions of Donald Trump on the campaign trail, why shouldn’t the American people demand assurances that Donald Trump – and all candidates for that matter—are mentally stable enough to become president of the United States.

More bluntly, why on earth should America’s leaders knowingly let a nut-case take over the White House?

At the very least, why not insist that that all the candidates undergo some kind of psychiatric examination? That would of course include Trump’s main rival, Ted Cruz—seemingly another mentally – challenged figure.