Time is not always governed by the calendar. The 20th century ran a few years shy of 100, getting a late start with the outbreak of World War I in 1914 and ending, depending on who you ask, either with the collapse of the Soviet Union in 1991 or the Sept. 11 attacks in 2001.

In the middle of that short century, however, the 1960s were a "long decade." The events and cultural markers we associate with the 60s are not neatly confined between 1960 and 1969 but stretch, as British historian Arthur Marwick has posited, from 1958 to 1974. Marwick chose the latter date, as he explains in The Sixties, because it was then "that the mass of ordinary people began to feel the effects of the oil crisis [which started in late 1973], because some of the crucial developments initiated in the 60s only culminated then ... and because only in August, with Congress drastically cutting aid to Saigon and Nixon resigning, did the anti-war movement feel it was achieving victory."

The felt boundaries of a decade, then, are not necessarily limited by its actual years. The tenures of presidents, the progression of war and peace, the course of economic booms and busts, even the meandering of style in clothes and music can all shrink or expand a decade beyond its normal limits. And I suspect, like the 1960s, the 2010s will be measured long.

I don't say this with pleasure. My sense is that many of us want this new year to be a clean break. We are politically exhausted and eager for a new era of normalcy, whatever our political affinities tell us that means. We are tired of a constant feeling of apogee, of careening from one crisis — one threat — to the next. Unfortunately, there is no reason to think 2020 has brought this wild decade to a close.

"I would say the current 'decade' essentially began with the 2008-2009 financial crisis," argues Jasmin Mujanović, a political scientist at Elon University whose tweet thread on the long 2010s provided the language I was seeking for this column. "Mind you, one could also make an argument for re-framing all of this in light of 9/11," Mujanović told me, "but I'm of the belief that the financial crisis was a watershed moment in its own right, one that carried with it a lot of the features and anxieties of the post-9/11 world but unleashed a new, still more existential form of politics in much of the West, in particular."

Particularly for my generation and our Boomer parents — I graduated college nine months after Lehman Brothers collapsed, and many of my peers saw their families' homes repossessed as they came into adulthood — 2008 feels like a clear dividing line, the first time 9/11 was superseded as a preoccupying catastrophe. But if the financial crisis started the 2010s, what closes the decade is difficult to predict.

I'm inclined to name 2021 as the soonest conceivable end date, a timeline only possible if President Trump loses his re-election campaign. Mujanović's forecast is longer. "I can't see most of the major dynamics of the present — the war in Syria, the rise of the Western far-right, Russian revanchism, American decline and Chinese ascendancy, the internal crisis of the European Union combined with the chaos of Brexit, the cataclysmic realities of accelerating climate change, etc. — playing themselves out before 2025," he said. "And realistically, I think we're going to be having many of the same conversations well into the 2030s." That would be a long decade indeed.

It is a strange thing to conceptualize a long decade while you're still in it, a bit like breaking the fourth wall of history to monologue to — well, everyone. But there is some value in thinking of our time this way. It adjusts our expectations for 2020, tamping down unrealistic hopes and fears alike. There will be change in the coming year, as in every year, but we can mostly anticipate continuity. Take a breath.

More practically, forecasting a long 2010s encourages taking the long view on what Mujanović called a "cluster of intertwined crises that demand our constant attention." Their resolution is not nigh. We will be dealing with present problems and their effects for years to come. "I think all of us would do well — especially those with real political influence and power — to step back and think about where we want the world to be in 20 or 30 years," Mujanović advised. That means thinking past the next election cycle and the one after that, which is basically contemplating eternity so far as the American polity is concerned. It is a contemplation we must brave.

My annual New Year's Eve cocktail party marked the end of the year and only the year. For whenever the end of the long 2010s may arrive, it won't be this New Year's Day. We aren't getting off that easy.