For the past several years in Europe, the dominant story in politics has been the crumbling center. From Britain to Hungary, right-wing populist and nationalist parties — and, to a lesser extent, left-wing populist parties — have surged at the expense of the traditional parties of the center left and center right.

Nowhere has that narrative been more alarming than in Germany, where the far-right Alternative for Germany (AfD) surged from nonexistence to third place in last year's election. As Angela Merkel's government has tottered, and her Christian Democratic Union-Christian Social Union (CDU-CSU) coalition has been pummeled in regional elections, there's been every reason to fear that right-wing populism could soon triumph in Europe's most powerful country and the one whose history should surely have inoculated it against the return of that particular plague.

But it's actually in Germany that the strongest counter-narrative to this story is also developing. The old established parties, the CDU-CSU and the Social Democratic Party (SPD), continue to sink in the polls and in public esteem. But the fastest-rising star isn't a populist alternative, but the vanguard of a new, more self-confident liberal center: the Greens.

It may seem strange to describe the Greens as a party of the center, given that they began as an pacifist and ecologically-oriented alternative to the established parties in the 1980s. And even as they entered national government in coalition with the SPD in the 2000s, they continued to be viewed abroad as a left-wing splinter group.

But they are a splinter group no more — and they have long since grown into the responsibilities of power. The Greens are now part of the governing coalitions of more than half of Germany's states and as the lead partner in the state of Baden-Württemberg. As you would expect of a mainstream party, they can work with both the right and the left, serving in coalition with the SPD in some states and the CDU in others. And based on the most recent national polls, if an election were held today they would be the second largest party in the Bundestag, garnering about 21 percent of the vote, versus 26 percent for the CDU/CSU and 14 percent for the SPD (based on an average of national polls for the month of November).

Of course, surges for the Greens have happened in the polls before. In 2010-2011, they several times polled within striking distance of the SPD, only to fade to fourth place by the time Germans actually voted in 2013. We're a long way from the next scheduled election, and the current surge — though substantially larger than any they've experienced before — could also prove ephemeral.

Still, why have the Greens succeeded? It's not because they're a rebranding of the mainstream party of the left. The SPD has struggled not only because of their presence in the coalition, but because the class politics that should be at their heart has long since given way to bureaucratic managerialism, leaving their working class base adrift (and to some extent drifting to the AfD as well as the left). The Greens, meanwhile, have prospered in this difficult political environment both where they have been in power, such as in the state of Hesse, and where they have been in opposition, such as in the state of Bavaria. They've thrived partly because of a reputation for integrity and a political culture that is distinctly anti-populist, eschewing the cults of personality that mark many alternative parties. And they've been able to create that political culture, I suspect, because the Greens actually believe in something, something deeper than politics. They are a party with the soul of a church.

By that, I don't mean to cast doubt on the Greens' rationality. There is an eminently rational case to be made that climate change is the single most important threat facing humanity today, one worth subordinating pretty much every other material concern to in order to fight. Voting Green is entirely defensible as a matter of pure enlightened self-interest.

What I mean, rather, is that the Greens are more than a party that represents a set of interests, or anything as rigid and ossified as an ideology. Rather, they are a party with a deep sense of core values that informs everything from their spending priorities to their foreign policy views to their frank and unequivocal embrace of immigration. Their political commitments start from a sense of what constitutes a good society, one that is ethical and well-ordered in terms of the relationship between states and peoples, and the relationship between humanity and the rest of the natural world.

The Greens have already amply demonstrated an ability to compromise and to govern moderately, and to focus on bread and butter issues as well as the causes for which they were founded. They've been able to do that without tearing themselves apart precisely because the debates around compromising or moderating on certain issues are happening inside the church, among believers, who share the conviction that those choices matter for reasons beyond their political efficacy.

In that sense, the Greens most closely resemble the CDU in its early years, when Konrad Adenauer led the party in the decades after World War II, and through which he rebuilt Germany as a democratic member of the family of Western nations. Adenauer believed that the revival of Christianity was essential to Germany's national survival and rebirth, and that National Socialism grew out of a Prussian state-worship that was essentially un-Christian. He was perfectly adept at practical compromise. Though a devout Catholic, he stood firmly for the CDU to be trans-denominational — and on the other hand, he led the fight to end de-Nazification. But his sense of politics was grounded in a sense of soul, his own and that of his people.

That's what I think distinguishes the Greens as well. It's why they're uniquely well-positioned to talk about patriotism as the love of a particular place and its ways, while remaining thoroughly progressive: Because those values are congruent with the environmentalism that is at their very heart. It's surely no accident that, according to an analysis from the Forsa research institute, about 40 percent of Green voters think of themselves as coming more from the right side of the spectrum rather than the left.

If the next German election were held today, no party would come close to a majority, and the only practical coalition would be between the CDU/CSU and the Greens. Could the party of Germany's Christian soul, and the party of its post-Christian soul, prove more durable partners than the present coalition? There's reason to think they might.