For America, 2016 was a dark year. The country was still at war. Our election was a brutal grudge match that left us more polarized than ever. Our closest allies were rocked by terrorism and turmoil. Adversaries toyed with our politics. Even the basic facts about life and science seemed to be in dispute.

However you voted, this was a year few would want to repeat. Now, as the calendar is about to turn, many of us look to the new year with a mix of hope and concern.

If you’re like me, this holiday season is a time for reflection, sometimes with anguish, about how we got here and where we’re going. I found comfort in the image at the center of the Christian faith, of an innocent baby arriving in a dark land — the beginning of a story that has been more powerful over the past 2,000 years than all the tyrants and tax collectors.

Americans are optimists, by birth or affirmation. We pledge allegiance to a country that is “indivisible, with liberty and justice for all.” We believe in “And the Fair Land,” the abundant nation evoked by the Wall Street Journal in its Thanksgiving editorial, which has been printed every year since 1961: “We can remind ourselves that for all our social discord we yet remain the longest enduring society of free men governing themselves without benefit of kings or dictators. Being so, we are the marvel and the mystery of the world.”

The year ahead will test how well the system devised by our founders works under stress. President-elect Donald Trump proposes radical changes welcomed by his supporters but feared by many who voted against him. He won’t succeed if he drives the country to the breaking point.

How hard will Trump push to undo existing laws and agreements? Will Congress play its role in checking raw executive power, or will Republican majorities be loyal to party first? Will officials who swear to protect and defend the Constitution demonstrate by their behavior in office that they mean it?

As Trump’s inauguration approaches, he remains a mystery to many of us. He seeks to be a disruptive agent of change, but what are the limits? What if Trump tries to place himself above the law? He wouldn’t be the first president to do so, but are the country’s institutions still strong enough to resist? What if he tries to subvert investigations of Russian hacking that are being conducted by our intelligence agencies and Congress? The cliche “profiles in courage” may actually get a test in 2017.

Trump’s comment Wednesday that “we ought to get on with our lives” despite Russian hacking sounded like a self-protective attempt to minimize an investigation that’s only beginning.

This coming year, the United States will face the severe strains that accompany change and political division. We’re a soft target for our adversaries right now — a country whose nerves are raw and jangled, whose tribal fault lines are exposed and easy to exploit.

Our national heroes are the men and women who get up every day and serve the country — in the military abroad, in schools and hospitals and fire stations at home. We want to be as steadfast in adversity as they are. We’ll find out in 2017 how healthy our body politic really is, and whether our democratic institutions remain resilient.

This holiday season, I got a burst of sunshine in a production of “Carousel,” the Rodgers and Hammerstein musical, at the Arena Stage in Washington. Many strands of our national myth come together in this story of a carnival barker who falls in love with a sweet, shy girl who works in a factory. It’s a hymn to blue-collar America, to rebellious young people who insist on being free spirits despite the prissy elitists and censorious prudes who want to tell them what to think. Like “Oklahoma,” it describes the America many of us have in our heads when we think about the way life used to be.

How did this quintessential American story of working people in Maine emerge? It was adapted from a 1909 Hungarian play. The 1945 Broadway version was written by two Jewish Americans and directed by an Armenian American. Nowadays, the phrase “melting pot” is sometimes taken as a “micro-aggression.” Not then.

When Trump says “Make America Great Again,” he evokes the national mythology that binds us together, whatever racial or other biases it may conceal. After a bruising 2016, perhaps this is a theme that we all can embrace. America is at its greatest when it’s united, confident and inclusive of all its citizens. Let’s hope that’s what Trump has in mind for this country. We need to be great in that way again.

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