Trump did not really make an incoherent mess of himself in his debate against the much smarter, more mature and better prepared Hillary Clinton: The microphone was “defective” and the moderator’s questions were “unfair.”

When Trump presents America as the setting of a postapocalyptic thriller, where cannibals and killers roam the streets and scary Asian or Arab villains extinguish innocent lives from far off palaces, he does so not because it resembles reality but because it resonates in the shrinking hearts of his voters. According to several studies, Trump speaks at a fifth-grade level. He seems incapable of anything more sophisticated. But his juvenile vocabulary offers stylistic enhancement to the worldview he sells, and his constituents embrace that. It is the worldview of the frightened child.

The stakes of the election are profoundly high because democratic governance requires a self-assured public of informed people making rational choices and willing to accept the burden of participatory citizenship. Democracy, in other words, is for adults. It also requires courage. Fear incites a fight-or-flight response, and fearful Americans have taken flight into the arms of an authoritarian — a paternalistic figure who absolves them of responsibility by blaming immigrants and others and who eases their burden by promising to “fix it like no one else.”

The child-grown-old versus adult dichotomy lies at the heart of British author Christopher Jackson’s brilliant new book on the presidential race, “The Fragile Democracy.” There is always a risk of losing relevance by the second when addressing current affairs, but Jackson has succeeded in the elevation of his analysis to philosophy by anchoring it in the virtues of the Enlightenment — the very virtues that the Trump campaign has placed under attack. Jackson’s comparison of America’s turmoil with the recent Brexit referendum in his homeland demonstrates that it is not only Americans who are “suspicious of complexity” or “cruel” in their desire to simplify the world so that it will conform to their ignorance.

Jackson believes that the current presidential race is about “enlightenment versus chaos.” What is lost on Trump supporters is that as authoritarians attempt to make the world simpler, they make it more chaotic. No one — not a theocratic dictator nor a megalomaniacal mogul — can control the events of the world and reduce the complications of life. As authoritarians try to exert their pull, the world slips further out of their grasp and they are forced to take more drastic measures. Such measures inevitably result in misery and catastrophe.

“Reason is still the best lamp against darkness and difficulty in the world,” Jackson argued. The celebration of reason is the adult perspective that scaffolds democratic governance. The Trump coalition rejects reason, caring little for the consequences.

Democratic presidential nominee Hillary Clinton is far from a perfect candidate, but she is an adult and as such vastly preferable to Trump. More important, the constituency that her victory would empower is much more conducive to the long-term survival of American democracy than the freakish collection of white nationalists, conspiracy theorists and ignorant tribalists that Trump has unleashed.

For all the contempt that Trump deserves, he has provided the invaluable if troublesome service of exposing certain unpleasant truths. There is now no doubt that large numbers of Americans, with a childlike resistance to diversity and democracy, are proud of their prejudice and willing to act on it. They hope to inject it, like a carcinogen, into the lungs of the body politic, eventually choking it.

Clinton’s election, if it happens, will not cause the anti-democratic forces on the march to turn around or reform themselves. For all the reasons to remain hopeful (the expansion of liberty and protection to more groups of Americans, the progressive orientation of most younger people, the increased focus on disparities of race and gender), our democracy remains fragile, largely due to the cowardly urge of many Americans to escape their lives and responsibilities. It has absorbed worse blows and prevailed in tougher times, but its survival demands vigilance — and adult supervision.