Pessimists often compare today’s troubled America to a tottering late Rome or an insolvent and descending British Empire. But medieval Europe (roughly A.D. 500 to 1450) is the more apt comparison.

The medieval world was a nearly 1,000-year period of spectacular, if haphazard, human achievement — along with endemic insecurity, superstition and two, rather than three, classes.

The great medieval universities — at Bologna, Paris and Oxford — continued to make strides in science. They were not unlike the medical and engineering schools at Harvard and Stanford. But they were not centers of free thinking.

Instead, medieval speech codes were designed to ensure that no one questioned the authority of church doctrine. Culturally or politically incorrect literature of the classical past, from Aristophanes to Petronius, was censored as either subversive or hurtful.

Career-wise, it was suicidal for, say, a medieval professor of science at the University of Padua to doubt the orthodoxy that the sun revolved around the earth.

Similarly, at Berkeley or Princeton, few now dare to commit the heresy of expressing uncertainty about whether man-caused global warming poses an immediate, existential threat to human civilization.

Today, a fifth of American households have zero or negative net worth. The shrinking middle classes struggle to service trillions of dollars in consumer and student debt to big banks — in the manner of medieval peasants.

In the medieval world, impoverished serfs pledged loyalty to barons in exchange for their food and housing on the manor. In the modern world, progressive government is the bastion that distributes entitlements on the expectation that the masses show their political fealty at election time.

In medieval Europe, widespread literacy disappeared. Superstition reigned in place of reason.

Despite spending some $11,000 per student each year, are we all that much different? In many polls, more than a quarter of Americans believe in astrology. A quarter think aliens have visited Earth. More than 40 percent can’t name their own vice president. Nearly three-quarters of Americans have no idea what the Cold War was about.

The ruling cliques of the medieval court were full of insider knaves and scoundrels, plots and intrigue. Compare the current scandals, lies and hypocrisies of our Beltway cloister in Washington.

Closeted scholiasts wrote esoteric treatises that no one read. These works were sort of like the incomprehensible “theory” articles of university humanities professors who are up for tenure.

To talk to the masses, the Latin-speaking elite spoke localized slang that would centuries later become English, French and German — the medieval version of our electronic grunts and made-up words on Twitter and email that are forming a new popular language.

Medieval Europe was fragmented into local and warring fiefdoms. Tribalism trumped state unity — not unlike America’s descent into separate red-state and blue-state cultures and identity politics.

With ancient borders long forgotten, medieval elites relied on massive walls, moats and keeps to stay safe — sort of similar to what we see with the present-day gated estates of Malibu and Silicon Valley.

Today’s zillionaire lords drive BMWs and fly in private jets instead of riding huge warhorses. They may wear jeans and flip-flops in place of robes and crowns, but their wealth and influence are as unlimited as the splendor of the lords of the medieval manor.

Facebook founder Mark Zuckerberg apparently does not assume that state law enforcement can guarantee the security of his estate. Instead, he has his own security personnel to keep out bounders — and buys up all the houses around his own in a postmodern effort to form a sort of premodern moat.

The great architects of the late Middle Ages could design majestic cathedrals at places such as Chartres and Rouen. But debt, incompetence and quarreling meant that their construction — unlike the earlier construction of the Parthenon — took centuries to complete.

The blueprints and mock-ups for California high-speed rail are as grandiose as the plans of medieval Gothic churches. But the reality of ever completing the project will require a half-century of cost overruns, lawsuits, and continual higher fees and taxes.

For their roads and water, isolated medieval fiefdoms relied on the crumbling ancient infrastructure of long-gone Rome.

In 21st-century America, we rely on — but could never again build — structures such as the Hoover Dam. It’s inconceivable that we could build, for instance, a new eight-lane, interstate super freeway system from coast to coast.

Medieval mass entertainment — puppeteering, mimes, jugglers, acrobats — was far different than the sort of entertainment that troubadours and bards performed for the lords. In our age, think of the gulf between the symphony and reality TV, quiz shows and the NFL.

There is one great difference, however, between the medieval and modern worlds.

People living in medieval times believed in transcendence and a soul, and sought to keep alive culture until civilization returned.

People living in modern times increasingly live for their appetites without worry about what follows – with little awareness of what has been lost and so not a clue about how to recapture it.

© 2016 TRIBUNE CONTENT AGENCY, LLC.