It remains difficult to predict who will be the eventual winner of France’s upcoming presidential elections, with the first round to take place April 23 and a runoff between the top two candidates set for May 7. Polls indicate that any of the four primary presidential candidates could emerge victorious: the traditional right’s François Fillon, the new centrist Emmanuel Macron, the far right’s Marine Le Pen, and the far left’s Jean-Luc Mélenchon. Importantly, the latter two support policies far outside the traditional French and European consensus, which French foreign policy has been based on for decades. Their extreme positions may lead to the end of French membership in both the European Union and the North Atlantic Treaty Organization (NATO), and consequently unravel the postwar effort to bind the European continent. Twenty-six years after the collapse of the Soviet Union, the demise of this European project would be a superb victory for the Kremlin. Incidentally, on March 24, President Vladimir Putin officially welcomed Marine Le Pen to Moscow.

The Fifth Republic, established by General Charles de Gaulle in 1958, created an institutional framework that gives the French president a pivotal role in developing and conducting foreign policy. All candidates refer to de Gaulle’s legacy in one way or another. As foundations of the president’s legitimacy, direct election by universal suffrage, control of nuclear weapons, and the power of appointment are parts of the domaine réservé that give the French president an unusually free hand compared to other democratic governments. Undoubtedly, this allows the president to affect lasting change and to manage international crises.

Yet, this can be a significant drawback when a newly elected president has no realistic vision or serious training in international affairs. Foreign policy is the area in which inconsistency, ideology, and ignorance are punishable offenses. The French public had high expectations that this election would allow for a debate on the European project with at least a modicum of seriousness, beginning with the premise that France is a constructive international player. Unfortunately, this has not proved possible in the current campaign due to political scandals that have engulfed two candidates—Fillon and Le Pen.

Since 1958, political consensus and continuity has prevailed on the main French foreign policy issues: strategic independence within an alliance system thanks to nuclear armament; the European project, which was founded on Franco-German reconciliation; and diplomatic multilateralism based on France’s permanent seat on the UN Security Council. This consensus is under severe pressure. Whoever he or she will be, the next French president will assume office at a time of deep internal and external crisis with France’s allies and partners, who are entertaining profound doubts about the seriousness of the country’s engagement in Europe.

At this point, two French idiosyncrasies must be noted. First, the current reconfiguration of globalization, which is being driven mainly by a global redistribution of power and wealth and by the growing pace of digitalization, is generally presented as the main threat to the so-called “French model.” This model of a regulated economy and strong public and social spending is based on an increasing disproportion between economic revenues and social expenses. Second, some candidates seem to believe that France could cut itself off from the world or that it could reverse the flow of globalization with its glorious vision of its role in the world. Revolutionary statements and bombastic universalism are deeply rooted in French political culture, at least during electoral periods.

However, realities do matter. As soon as the new president is elected, he or she will face three challenging realities. The first is France’s place in the NATO security alliance. Even if unappreciated by the French public, relations with Washington and London have been pivotal for France’s security policy since 1917, and the so-called P3 continues to design France’s security policy in terms of nuclear cooperation and intelligence sharing. The new French president will have his or her first international meeting at the NATO summit in Brussels on May 25, just weeks after taking office. After stating that NATO is no longer obsolete, U.S. President Donald J. Trump is expected to participate in this summit as well. If Le Pen or Mélenchon are elected, they would need to express their intentions regarding France’s future role in the alliance at this summit without any real preparation.

The second reality is French relations with the EU and Germany. Contrary to NATO, this reality is well known to the French public. The 1957 Treaty of Rome initiated reconciliation between France and Germany and was the cornerstone of the European project. However, the two countries do not see eye to eye because of their economic asymmetry, which has dramatically increased over the last decade. In 2016, France’s trade deficit with Germany deepened to around 14 billion euros, its highest point in a decade. In view of France’s sluggish economic growth, it remains to be seen whether it really has a choice when it comes to breaking ties with the EU and Germany. In the past, strong political will on both sides served to gloss over the structural differences between Paris and Berlin. This political will is likely to be tested before summer.

The third reality is military spending. Like its European allies, France is facing a deteriorated strategic environment with diverse threats ranging from terrorism on its soil to coercive military strategies in regions including the Levant and the Sahel. To put it bluntly, if the financial resources devoted to defense are not significantly increased, France’s military model of strategic autonomy, which is at the core of its international positioning, will soon be at risk. Le Pen has proposed increasing the defense budget to 2 percent of GDP by 2018, and closer to 3 percent by 2022. She has stated she intends to protect and maintain the two legs of France’s nuclear deterrent: submarines and aircraft. On the other side of the political spectrum, Mélenchon remains unclear on his preferred defense budget, only refusing to comply with NATO’s standard of 2 percent of GDP. However, he has said he intends to make cuts to funding for aircrafts.

There are of course other pressing foreign policy issues, which include sovereign debt, trade, energy and climate, digital autonomy, migration, as well as French policy toward Africa, Asia, and Russia. But everything starts in Europe. As a founder of the EU and a first-rate power able to exert influence outside Europe, France carries weight in European debates. If the next president chooses to transform France’s existing alliances without any credible alternative or real preparation, these will be huge risks in a context of global strategic instability. A realignment of this magnitude would weaken, and possibly destroy, the Western community and would mark a sharp break from de Gaulle’s legacy.

To read more, visit the new French Institute of International Relation’s report, Foreign Policy Challenges for the Next French President.