BERLIN – This year and next, voters in leading Western democracies will make decisions that could fundamentally change the West – and the world – as we have known it for decades. In fact, some of these decisions have already been made, the main example being the United Kingdom’s vote in June to leave the European Union.

Meanwhile, Donald Trump in the United States and Marine Le Pen in France could very well win their countries’ upcoming presidential elections. A year ago, forecasting a victory by either would have been considered absurd; today, we must admit that such scenarios are all too possible.

The tectonic plates of the Western world have started to slip, and many people have been slow to realize the potential consequences. After the UK’s Brexit referendum, we now know better.

The UK’s decision was a de facto decision against a European order of peace based on integration, cooperation, and a common market and jurisdiction. It came amid growing internal and external pressure on that order.Internally, nationalism has been gaining strength in nearly all EU member states; externally, Russia is playing great-power politics and pushing for a "Eurasian Union” – a euphemism for renewed Russian dominance over Eastern Europe – as an alternative to the EU.

Both of these forces threaten the EU’s structure of peace, and the bloc will be weakened further without the UK, its traditional guarantor of stability. The EU is the linchpin of European-Western integration; so its weakening could cause a European reorientation toward the East.

This outcome would become even more likely if Americans elect Trump, who openly admires Russian President Vladimir Putin and would accommodate Russian great-power politics at the expense of European and transatlantic ties. Such a Yalta 2.0 moment would then fuel anti-Americanism in Europe and compound the geopolitical damage suffered by the West.

Likewise, a victory for the far-right nationalist Le Pen next spring would signal France’s rejection of Europe. Given France’s role as one of the EU’s critical foundation stones (along with Germany), the election of Le Pen would most likely mean the end of the EU itself.

If the UK and the US turn to neo-isolationism, and if France abandons Europe in favor of nationalism, the Western world will become unrecognizable. It will no longer be a bastion of stability, and Europe will descend into chaos indefinitely.

In this scenario, many would look to Germany, Europe’s largest economy. But, though Germany would pay the highest economic and political price if the EU collapsed – its interests are simply too interwoven with the EU’s – no one should hope for German renationalization. We all know what destruction and calamity that can bring to the continent.

Geopolitically, Germany would be consigned to an uncertain man-in-the-middle status. While France is clearly a Western, Atlantic, and Mediterranean country, Germany, historically, has oscillated between East and West. In fact, this dynamic was long a constitutive element of the German Reich. The East-or-West question wasn’t finally decided until after Germany’s total defeat in 1945. Following the establishment of the Federal Republic in 1949, German Chancellor Konrad Adenauer chose the West.

Adenauer had witnessed the full scope of the German tragedy – including two world wars and the collapse of the Weimar Republic – and he considered the young Federal Republic’s ties with the West to be more important than German reunification. For him, Germany had to abandon its man-in-the-middle position, and thus its isolation, by irreversibly integrating with Western security and economic institutions.

The post-war Franco-German rapprochement and European integration under the EU have been indispensable elements of Germany’s Western orientation. Without them, Germany could return to a strategic no man’s land, which would endanger Europe, stoke dangerous illusions in Russia, and force Germany itself to deal with unmanageable challenges confronting the continent.

Germany’s geopolitical orientation will be a central underlying issue in next year’s general election. If German Chancellor Angela Merkel’s own Christian Democratic Union ousts her because of her refugee policy, the party will likely tack to the right in an effort to win back voters it has lost to the anti-immigrant, populist Alternative for Germany (AfD).

But any move by the CDU to cooperate with the AfD, or to validate its arguments, would spell trouble. The AfD represents German right-wing nationalists (and worse) who want to return to the old man-in-the-middle position and forge a closer relationship with Russia. Cooperation between the CDU and AfD would betray Adenauer’s legacy and be tantamount to the end of the Bonn Republic. Meanwhile, there is similar danger from the other side of the aisle, because any prospective CDU-AfD coalition would have to rely on Die Linke (the Left Party), some of whose leading members effectively want the same thing as the AfD: closer relations with Russia and looser or no integration with the West.

One hopes that we will be spared this tragic future, and that Merkel will retain her office beyond 2017. The future of Germany, Europe, and the West may depend on it.

Joschka Fischer was German Foreign Minister and Vice Chancellor from 1998-2005, a term marked by Germany’s strong support for NATO’s intervention in Kosovo in 1999, followed by its opposition to the war in Iraq.

Copyright: Project Syndicate.