On Nov. 9, 1989, East German border guards opened the Berlin Wall and changed the trajectory of history. The fall of the wall marked the beginning of the end of the Cold War. It was also a moment of hope and possibility. Even before the wall came down, Soviet leader Mikhail Gorbachev was making the case for a “common European home” in which the United States and the Soviet Union would both play a role, winning cautious praise from Western leaders. “I think we have come out of a period of cold war, even if there are still some chills and drafts,” Gorbachev said in June of 1989. “We are simply bound to a new stage of relations, one I would call the peaceful period in the development of international relations.”

Thirty years later, those “chills and drafts” are intensifying. The United States and Russia are now locked in a new Cold War that represents a grave danger to humanity. Together the two countries possess nearly 14,000 nuclear weapons, about 1,800 of which are kept on hair-trigger alert. According to the Bulletin of the Atomic Scientists, the risk of “destroying our world with dangerous technologies of our own making” is at its highest level since 1953. And, unlike in 1989, there is little hope that tensions will thaw any time soon.

President Trump claims that he’d like to “get along” with Russia, but his administration has increased the level of nuclear peril. This year, the United States withdrew from the Intermediate-Range Nuclear Forces (INF) Treaty signed in 1987, a move that nonproliferation experts warned could lead to a new arms race. Now, it appears that the New START Treaty, set to expire in February 2021, could be the next to go. The New York Times reports that the Trump administration “intends to let it expire unless it can be broadened” to include China, which is “not interested.”

That means that U.S. and Russian nuclear modernization could proceed unchecked, leading to heightened instability in the years ahead. In the best-case scenario, a newly elected Democratic president would have just a few weeks upon taking office to extend the agreement. The danger of nuclear confrontation, Gorbachev warned in a recent interview with the BBC, “is colossal.”

Equally worrying are hardening divisions in Europe. NATO forces have now extended their presence to Russia’s very borders, where there are daily shows of bravado on both sides. Worse yet, Ukraine is now torn by a civil war between the U.S.-backed government and Russian-supported separatists in the eastern Donbas region. According to the Office of the U.N. High Commissioner for Human Rights, more than 13,000 people have been killed since the war began in 2014, with another 30,000 wounded or injured.

How did we go from the hope of 1989 to a new Cold War?

Certainly, U.S. foreign policy played a critical role. In the years following the fall of the wall, two triumphalist ideas dominated U.S. foreign policy — the geopolitical idea of the “end of history” and spread of liberal democracy, and the related concept of the United States as the “indispensable nation.” Together these ideas contributed to what became known as the unipolar moment. NATO violated assurances given to Russia that it would not expand “one inch” eastward, a provocation that yielded predictably disastrous results. The legendary Cold War diplomat George Kennan warned in 1998 that NATO expansion would cause Russia to “react quite adversely” and was “a tragic mistake.”

Russia also bears responsibility for squandering the opportunity that the Berlin Wall’s opening provided. In the post-Gorbachev era, Russian leaders allowed the pursuit of democratic reforms to give way to a system of corrupt oligarchic capitalism that bred poverty and discontent. Meanwhile, the bloody Chechen war increased Western skepticism of Russia’s commitment to human rights and fears of Russian revanchism.

More important than who’s to blame, however, is where the United States and Russia go from here. Friendship between our countries may not currently be on the table, but diplomacy and dialogue should be. This moment calls for constructive engagement to de-escalate nuclear tensions. It also calls for renewed thinking about how to revive Gorbachev’s vision of a “common European home” for the 21st century.

One place to begin would be a renewed push for a peace settlement in Ukraine. The election of Volodymyr Zelensky, who ran on a peace and anti-corruption platform, along with his initial overtures to Moscow, has opened up an opportunity to end the military conflict and implement the political reforms provided for in the Minsk agreements. What has been missing so far has been active U.S. and Russian cooperation to complement French and German diplomatic efforts, namely U.S. pressure on Kyiv to implement autonomy for the Donbas and to halt its military operations, and Russian pressure on the separatists to give up their more ambitious goals of independence. The impeachment hearings have complicated any U.S. efforts to influence Ukrainian policy, but Democrats and Republicans need to understand that Ukrainian interests would best be served by a more constructive U.S. policy.

Support for a less adversarial U.S.-Russia relationship may not be popular. As I have argued in the past, though, it is sober realism. While the outlook today is bleak — with the new division of Europe, with billions being wasted on military buildup and new nuclear weapons, and with war and suffering in Ukraine — the anniversary of the fall of the Berlin Wall is a timely reminder that there was, and still is, an alternative.

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