An employee arranges a European Union flag in the Europa building in Brussels on Feb. 23. (Dario Pignatelli/Bloomberg)

The defenders of what’s called the “liberal international order” have recently suffered setbacks from adversaries inside and outside their home countries. But those who want to see the Western-led post-World War II system survive or even thrive are plotting its resurrection.

When the United States and European countries came together in the second half of the 20th century to build multilateral relationships and institutions to strengthen and spread liberal values such as rule of law, democracy, open markets and human rights, it was an aberration. The project ran counter to centuries of international politics based on brute strength, solipsism, greed and war. In France this weekend, former White House official Stephen K. Bannon told far-right nationalists that “history is on our side” — and he wasn’t entirely wrong.

Former top White House strategist Stephen K. Bannon spoke to supporters of France’s far-right National Front March 10 in Lille, France. (Reuters)

While Bannon was working to undermine what he and his like deride as “globalism,” a group of American and European officials, lawmakers and experts were meeting here to figure out how to save it. The German Marshall Fund’s Brussels Forum kicked off with a call to action.

“We lost sight of what it took to create this international order and what an act of defiance of history and even defiance of human nature this order has been,” author Robert Kagan told the group. “We have the capacity to push back — we just need to understand the pushback needs to start occurring.”

Internationalists share a realization that the order is at grave risk, and along with it the seven decades of relative growth, prosperity and peace it provided. Nationalism and populism are ascendant in the United States and Europe. Authoritarianism led by Russia and China is on the march around the world.

The West assumed after the Cold War that worldwide acceptance of liberal values was inevitable, but alas, history did not end. Geopolitical competition resumed. The negative effects of globalization drove discontent with the liberal open-society model. Adversaries took advantage. Then came the duel shocks of Brexit and the election of Donald Trump.

Some say that liberal democracy simply didn’t address the needs and desires of its populations. Others say the liberal international order was never truly liberal, international or orderly. The mission to defend it must include acknowledging and addressing those shortcomings.

But the first task is simply to “keep it alive,” Sen. Chris Murphy (D-Conn.) told the forum. Active U.S. government leadership will be impossible so long as Trump is president because he doesn’t support things such as projecting liberal values into other countries, trade liberalization or multilateral institutions.

Therefore, the task at hand for defenders of the liberal international order is to “build new alliances within our societies and between our societies,” Murphy said.

Bannon’s project is to unite nationalists on the left and right against the system. In reaction, internationalist Democrats and Republicans are renewing their alliance to fight back. Rep. Michael R. Turner (R-Ohio) told me that connecting the mission back to the American people was crucial.

“Democracies lead by their electorates coming along and supporting the agenda and the direction of the Western structure,” he said. “That’s what had been missing for a while.”

The transatlantic alliance must also recognize the failure of its decades-long effort to court Russia and China to join the rules-based order. Democracies must once again stand up to and resist authoritarian efforts to undermine Western institutions and values.

The Russian government is attacking democracies and seeking to undermine the liberal order on a constant basis. China’s increasingly aggressive leadership is touting its program of state-controlled modernization as a model for the developing world, while it works to reset global norms in its own interest.

As far as they are concerned, the liberal international order was always exclusionary and never a viable end state for the entire world.

“From the very beginning, this was a Western project and Western-centered,” said Wang Dong, an international relations professor at Peking University. “This concept of liberal international order is insufficient and inaccurate in terms of describing what kind of order we are in.”

Even if proponents are successful in defending the Western system from internal and external attack, it will be forever changed. We can no longer expect that the principles of liberal democracy will expand across the globe. We can no longer assume the United States will carry the bulk of the burden.

But the system the Atlantic community built has a half-century head start on its challengers. Shoring up its foundations by reforming multilateral institutions, addressing the grievances of those left behind economically, defending the independence and integrity of the free media, and protecting the mechanics of democracies — such as elections — are a good start.

The liberal international order is far from perfect, but it is preferable to the alternative, an international system ruled by naked self-interest and tyranny of the powerful. The new alliance to defend it is mobilizing now. The stakes couldn’t be higher.

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