While the United States is still coming to terms with President-elect Donald Trump’s potential domestic and foreign policy, U.S. allies worldwide are becoming increasingly nervous about the incoming administration’s stance toward U.S. alliance commitments. Spurred by Trump’s warm words for Russian President Vladimir Putin, his implicit threat that Washington could scale back U.S. defense commitments to Europe if NATO members do not pay more for their own security, and his lax remarks that certain U.S. allies should perhaps be allowed to go nuclear, some prominent voices in Germany are suddenly openly flirting with the nuclear option.

Ulrich Kühn Ulrich Kühn is a nonresident scholar at the Carnegie Endowment for International Peace, and the head of the arms control and emerging technologies program at the Institute for Peace Research and Security Policy at the University of Hamburg. More > @DrUlrichKuehn

Given the country’s long-term support of nuclear disarmament, a debate about a possible German nuclear deterrent is virtually unprecedented. So far, these voices represent an extreme minority view—currently, neither the government nor the vast majority of German experts is even considering the possibility of acquiring nuclear weapons—but with continued uncertainty about Trump’s commitment to Europe, this could change during the coming years.

The Pro-Nuclear Arguments

Just three days before the U.S. elections, an op-ed in Germany’s largest left-leaning news outlet, Spiegel Online, mused about the possibility of Germany pursuing its own nuclear weapons if NATO were to break up in the aftermath of a Trump administration’s withdrawal from the alliance.

Two weeks later, Reuters quoted Roderich Kiesewetter, a senior member of Chancellor Angela Merkel’s Christian Democratic Union and a high-ranking member of the Bundestag (national parliament), saying that “if the United States no longer wants to provide this [nuclear] guarantee, Europe still needs nuclear protection for deterrent purposes.” Given Trump’s earlier statements, Kiesewetter continued, “Europe must start planning for its own security in case the Americans sharply raise the cost of defending the continent, or if they decide to leave completely.” His suggestion: a Franco-British nuclear umbrella for Europe, financed through a joint European military budget. Under such a scheme, Germany would have to contribute a large amount to the overall costs of such a European deterrent. Further clarifying his remarks, Kiesewetter later pointed out that Europe does not need additional nuclear powers.

On November 28, Germany’s most influential conservative newspaper, the Frankfurter Allgemeine Zeitung, opened with an op-ed by one of its publishers, Berthold Kohler, preparing Germans for “the unthinkable.” Continued Russian and Chinese attempts to expand their spheres of influence, coupled with a possible retreat of the United States, would amount to a “continental shift,” the author argued. According to Kohler, the stern implications for Berlin, which for many years relied on the approach of “Frieden schaffen ohne Waffen” (“build peace without weapons”), would be obvious: if Germany wants to successfully bargain with the Kremlin, he implies, it has to be able to credibly defend its allies (which is an interesting hint at the changed power relations in Europe). Kohler concludes that this could mean increased defense spending, a return to conscription, the drawing of red lines, and an indigenous nuclear deterrent. He is quick to insinuate that the French and British arsenals are currently “too weak” to take on Russia and China.

The Two Paths

Even though these remarks and op-eds do not build or comment on each other, they begin to reveal contours of a debate. One can see two paths of proposed action if the United States were to withdraw or openly question its security guarantees: a European nuclear option and a German nuclear option.

Following Kiesewetter’s suggestions, a potential European nuclear option could be interpreted as an extreme, though not logically conclusive, part of a larger ongoing effort to give the European Union more credible and integrated defense structures. German Minister of Defense Ursula von der Leyen is already lobbying for a bigger EU global security role and higher defense spending. There is little doubt that these efforts are also a reaction to Trump’s campaign comments. But more so, they represent a change in German foreign and security policy dating to 2013, when President Joachim Gauck cautioned Germans that “in a world full of crises and upheaval, Germany has to take on new responsibilities.”

In contrast, a potential indigenous German nuclear option is by no means grounded or linked to any ongoing political debate about Germany’s role as a security provider for Europe. Nevertheless, it is indeed a reflection—though an extreme and perhaps hysterical one—of the multiple crises and threats Europe is facing. These include, inter alia, an increasingly aggressive and militaristic Russia, the war in eastern Ukraine, the British Brexit vote, the war in Syria and the related refugee crises, and the heavy-handed authoritarian rule of President Recep Tayyip Erdoğan in Turkey.

Against this background, certain segments of the German strategic community seem deeply concerned about the uncertain effects of four (or eight) years of U.S. foreign and security policy under Trump. Not completely without reason, their criticism of him points to the fact that extended nuclear deterrence rests on a fragile, psychological bargain between the provider (the United States), the recipient (the NATO allies), and the addressee (Russia), which can only be upheld if all sides believe to a certain degree in the credibility of the deterring threat. Trump’s questioning of the continuity of U.S. security commitments places the whole bargain under stress. In this context, musing about a German deterrent could be interpreted as nuclear signaling to both Washington and Moscow.

The Current Realities

Notwithstanding the recent public airing of nuclear flirtations, powerful and convincing arguments speak against a German or non-NATO European nuclear option. All things nuclear are highly unpopular among ordinary Germans. In a recent poll, 85 percent of Germans spoke against the continued deployment of U.S. nuclear weapons in Germany. More than 90 percent approved the idea of an international ban on nuclear weapons. Even among policymakers, nuclear weapons policies have always been dealt with in a cautious and sometimes skeptical way. The 2009 coalition contract of Merkel’s ruling conservative party, for instance, held out the prospect of Germany working within NATO on a full withdrawal of U.S. nuclear weapons from German soil.

But since the Russian annexation of Crimea, the German government has been fully supportive of NATO’s nuclear-sharing arrangements and opposes the latest push in the United Nations toward a nuclear weapons ban treaty. Musings about a European deterrent, as articulated by Kiesewetter, would run counter to German efforts to remind the Trump administration of the value of NATO’s Article 5 commitments and the U.S. role as a security provider for Europe. In fact, they could give Trump carte blanche to argue that if Europe were to have its own deterrent, then why would it need Washington’s guarantees? It is also not clear how a Franco-British deterrent for Europe could take shape with London currently exiting from the European project.

In addition, Berlin just announced an increase in its defense spending by 8 percent in 2017, taking defense expenditures to 1.22 percent of its GDP. This is a significant increase, even though Germany remains considerably below its NATO commitment of spending at least 2 percent of its GDP on defense. Nevertheless, Germany can point to its efforts in the upcoming consultations with the new Trump team to counter criticism about its defense commitments to NATO. A possible German nuclear option would only distract from the core message that Germany is ready to take on more responsibility within the alliance and Europe as a whole.

Even if Germany was to attempt to go nuclear, the hurdles would be extremely high. Although the country is one of the most technically advanced nations in the world and it theoretically possesses enough fissile material for a nuclear device, the enormous financial and political costs that would come with such a decision would most likely outweigh any perceived benefit.

There are also many political-legal obstacles. Germany would have to withdraw from or seek to change the 1990 Treaty on the Final Settlement with Respect to Germany (also known as the Two Plus Four Treaty), which it signed together with France, the Soviet Union, the United Kingdom, and the United States. In that agreement, the reunified Germany reaffirmed its “renunciation of the manufacture and possession of and control over nuclear, biological, and chemical weapons.” In addition, Berlin would openly violate commitments under the international Treaty on the Non-Proliferation of Nuclear Weapons, the International Atomic Energy Agency, and the European Atomic Energy Community.

From Fringe to Mainstream

Obviously, current German nuclear flirtations represent a fringe view, but they are an important early warning sign. These flirtations were carried by Germany’s biggest left-leaning and conservative media outlets. In addition, Kiesewetter is not a backbencher or low-ranking politician from a small party. As a former Bundeswehr (armed forces) general staff officer; former chairman of the Subcommittee for Disarmament, Arms Control and Non-Proliferation of the Bundestag; and current spokesperson of the Committee on Foreign Affairs, he is well-versed in foreign and security policy matters. That a person of his stature would raise such a view is reason enough for concern.

Further, extreme views on nuclear matters do not always remain at the fringes. As the case of South Korea demonstrates, external shocks such as the repeated nuclear tests by North Korea in 2013 can quickly move formerly fringe positions to the center stage of public attention. Once in the mainstream, it can be difficult to put such sentiments to rest, particularly when the underlying security concerns remain.

To be clear, the Merkel administration is far from considering a European or German nuclear option, and other major political parties on the left are traditionally strong opponents of a more muscular nuclear weapons approach. For example, Rainer Arnold, defense spokesman for the ruling coalition partner of the Social Democrats in parliament, was quick to dismiss Kiesewetter’s suggestion as “off base.” In fact, for decades, Berlin acted as a staunch advocate of nuclear disarmament and nonproliferation policies, and isolated instances of German proliferation signaling were extremely rare. But their now sudden and unexpected occurrence is telling with regard to the devastating effects of Trump’s loose and uninformed talk about U.S. alliance commitments and long-standing American nonproliferation policies.

Beyond those more narrow observations, the “Trump shock” and its effects—which caught most German policymakers off guard—point to U.S. allies’ wider concerns about America’s role in the world and the likely period of unpredictability and volatility ahead. Underlying these perceptions and developments are strategic discontinuities that can occur quite rapidly and result in previously unimaginable developments. A U.S. retreat from long-held, global political and normative positions would be such a sudden discontinuity. Germany’s final acceptance of the role of a benevolent hegemon in Europe, in combination with the British retreat, would be another. Combined, they could give rise to alternative policy concepts and cognitive adjustments. The current German nuclear flirtation is just one, and certainly not the last, sign of the changing European security landscape.