An American flag in the aftermath of a tornado in Texas on Dec. 27. (Laura Buckman/Agence France-Presse/Getty Images)

You probably noticed that 2015 was pretty weird. But hey, it’s a brand-new year — a fresh start, a blank slate, an unwritten script. In 2016, what could possibly go wrong?

Uh, where to begin?

My fingers balk at typing the words “President-elect Trump” because I don’t think such a thing will actually happen. But at this point I’m wondering how to justify ruling anything out.

A year ago, was there anyone on earth who predicted that Donald Trump would utterly dominate the Republican presidential race? That the boastful billionaire would be setting the nation’s political agenda? That Jeb Bush, armed with more campaign money than he could possibly spend, would be drifting helplessly toward the single-digit wings of the crowded debate stage?

Nobody saw this coming, least of all the GOP establishment grandees who, as I wrote in August, are working their way through Elisabeth Kübler-Ross’s five stages of grief. First there was denial (“What a weird dream; maybe it was something we ate”), then anger (“He’s a clown, he’s a jerk, he should be drawn and quartered”), then bargaining (“Okay, okay, we give up on immigration reform”). Now party elders seem to be sinking into the fourth stage, depression.

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I have no idea whether they’ll have to reach the final stage, acceptance. Trump’s legions turn out for his revivalist-style rallies, but will they actually vote? If they do — and if the establishment-approved candidates keep pulling one another down like crabs in a barrel — then Trump is the likely GOP nominee. There, I said it.

That doesn’t make him our likely next president, though. Most Americans are appalled by notions such as forcibly deporting 11 million undocumented migrants or hanging a “No Muslims Allowed” sign on the Statue of Liberty. Quite a few dyed-in-the-wool Republicans, asked to support a candidate whose platform amounts to ethnic cleansing, surely would sit this one out — or even vote for the Democratic nominee, probably Hillary Clinton.

Trump vs. Clinton could be a wipeout defeat for the Republican Party on the scale of the 1964 Barry Goldwater debacle. The only caveat? See above re: absolutely ruling anything out.

What else could go wrong in 2016? Well, politics isn’t the only realm in which we have to shift our thinking from “no way” to “please make it stop.” Climate is another. Scientists confidently predict that 2015 will prove to have been the hottest year on record, perhaps by a considerable margin. And this week, temperatures at the North Pole may have reached the melting point — roughly 50 degrees above normal for this time of year.

Also this week we’ve had deadly tornadoes in Texas, bad flooding in the Mississippi Valley, worse flooding across South America and hurricane-force winds in the North Atlantic. On the bright side, there’s been no plague of locusts, far as I can tell.

It is true that the proximate cause of most of this anomalous weather is believed to be an unusually strong El Niño phenomenon in the Equatorial Pacific. I am obliged to include the disclaimer that no one weather event can be definitively blamed on climate change — not even the fact that I saw people in Washington wearing shorts and sandals on Christmas Eve.

That said, let’s be real. At this point, anyone who rejects the scientific consensus on human-induced global warming is either a blinkered ideologue, a Republican presidential candidate or both.

Climate scientists have long predicted that one impact of higher global temperatures will be to make extreme weather more common and unpredictable — and more extreme. With that monster El Niño on the loose, weather in 2016 could be even wilder and woollier.

In other news, what could go wrong in Congress is obvious; the same things go wrong every year. What could go wrong in foreign affairs is too depressing to contemplate.

So maybe it’s better to think about what could go right.

The economy continues to grow — slowly, perhaps, but steadily. Crime is at or near historical lows. About 90 percent of Americans have health insurance, which is closer to universal coverage than we’ve ever been. Budget-busting medical costs have slowed their ranks’ rise. These and other positive trends should continue, as meanwhile the nation lives through an election campaign that will not be able to dodge issues of fundamental importance.

In 2016, we’re likely to see an exercise in democracy that is passionate, messy, at times ugly — but vitally important. Happy New Year, and note that the seat-belt light will be on through November.

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