Based on the results of the first round of the French legislative elections, Jordan Bardella and Marine Le Pen’s Rassemblement National, and their allies in the ‘Union of the far-right’ (Union de l’extrême droit or ‘UX’) faction of Les Républicains, are on course to be the largest party in the French National Assembly. In the first round, the alliance of the radical right collectively came first in an astonishing 297 of the 577 seats, securing 33.15 per cent of the vote, and winning 37 seats outright. They will now go forward into runoffs in 444 more constituencies, compared to 414 for the left wing New Popular Front and 321 for Emmanuel Macron’s centrist alliance Ensemble.

After the second round on 7^th July, Bardella and Le Pen’s alliance is set to hold somewhere between 230 and 280 seats, potentially putting them just nine seats shy of an absolute majority and the capacity to form a government for the first time in the history of the Fifth Republic. More likely, however, is that the Rassemblement National and UX will emerge from the elections as the largest party in a National Assembly in which no one can command a majority.

Assuming that he does not resign the presidency, some commentators have recently suggested that in such a scenario President Macron’s strategy is to allow the Rassemblement National to form the government and discredit themselves as a serious alternative to Renaissance when expectations about what a Le Pen or Bardella led government might achieve collides with reality. But this approach seems unlikely, not least because Bardella has explicitly ruled out forming a minority government.

Since the first emergence of the Rassemblement National as the ‘Front National’ in the 1970s under Jean Marie Le Pen – father of the current leader – the party has been held apart from the French political mainstream, separated from power by a ‘cordon sanitaire’. Under this informal and unwritten constitutional convention, the far-right can never be allowed to enter government, and mainstream or ‘constitutional’ parties are obliged to cooperate in order to prevent them from holding power.

If Macron were to break with this, either in pursuit of the kind of Machiavellian gambit described above or because the Rassemblement National had won an outright majority, the foundational political assumptions of the Fifth Republic would come into question. Macron would be compelled in this scenario to ‘cohabit’ across the cordon sanitaire and share the government with a party that he has explicitly identified as a threat to the Republic and the Constitution.

Cohabitation is not unheard of in French politics. It occurred after the 1986 elections, when the Socialist president, Francois Mitterrand, was forced to cohabit with the Gaullist Jacques Chirac as Prime Minister. From 1993-1995 when Mitterrand cohabited again with the centrist Édouard Balladur, and from 1997-2002,  then President Chirac had to cohabit with the Socialist Lionel Jospin.

But these were cohabitations between ‘constitutional parties’ which recognised one another as legitimate potential parties of government. By contrast, both Macron and his opponents on the left view Le Pen’s party as fundamentally illegitimate and as a potential threat to the constitution, the republic, and democracy itself. With such unbridgeable conflicts between them, it seems improbable that Macron could countenance appointing a government led by the Rassemblement National unless he had no other choice.

Under Article 8 of the French Constitution, the president possesses absolute discretion as to their choice of prime minister. Where a party wins a majority, it is certainly convention that the prime minister will be the leader of that party, since the National Assembly can remove them, a power which the president does not possess. But the president is not obliged to follow this convention.

What happens if no one wins a majority? Precedent dictates that the leader of the largest party has an opportunity to form a coalition, but the president is under no obligation to invite them to do so – and there is precedent from French constitutional history that they might refuse to do so if they see the party as a danger to the constitution.

In 1952, amidst circumstances now largely forgotten in France, the then president of France’s Fourth Republic, Vincent Auriol, refused to appoint Charles de Gaulle as prime minister – even after de Gaulles’ insurgent and ‘anti-parliamentary’ Rassemblement pour la République won the most seats in the National Assembly – because Auriol felt that de Gaulle represented a threat to the constitution. General de Gaulle’s plurality of legislative seats, Auriol claimed, did not compel him to act as the ‘Hindenburg of the fourth republic.’ President Macron might, quite fairly, ask why the Rassemblement National’s technical victory should oblige him to play that role in the fifth.

There are pragmatic reasons to think Macron will follow such a course. A Rassemblement National government, likely led by Jordan Bardella, would almost certainly be unable to command a majority in the National Assembly. Indeed, although the principle that the mainstream parties should set aside their differences to prevent the far right from winning power has begun to fray in recent years, particularly with the refusal of Renaissance to endorse left wing candidates in the 2022 legislative elections, the taboo on cooperating with the extreme right remains. The prospect of Renaissance and the Rassemblement National cooperating remains unfathomable.

What, then, are the possible alternatives? One is that Macron appoints a prime minister from the – projected – second largest group in the National Assembly, the New Popular Front of the moderate and far left loosely led by Jean-Luc Mélenchon of La France Insoumise. But since 2022, Macron and Renaissance have erected something akin to a cordon sanitaire to their left.

On one side of this cordon lie the Socialists, an acceptable coalition partner but by far the weaker party in the New Popular Front; on the other lies La France Insoumise, with whom the Macronists are reluctant cooperate. And whilst Macron’s prime minister, Gabriel Attal, has announced the withdrawal of Ensemble candidates in races where they came third to the far-right and the left, not all in the Macronist camp are supportive of this new constitutional alliance. Indeed, Macron’s former prime minister, Édouard Phillipe, has urged the French to vote against extreme candidates ‘opposed to liberty and the rule of law’, a category in which he pointedly included both the Rassemblement National and La France Insoumise. Any hopes for a ‘constitutional coalition’ to keep the far-right out of power risk running aground on the rocks of antipathy between the centre and the far left.

That leaves only one option: that Macron appoints a prime minister from a party of the broadly construed centre, or even a ‘technocratic’ non-party Prime Minister, who will probably not be able to command a majority in the National Assembly, perhaps as a provisional measure until he can call new elections again in one year. As president this is entirely within his prerogative, but it bodes ill for the government of France.

Although French presidents are often portrayed as de facto monarchs, without the support of a parliamentary majority, presidential authority over domestic policy is extremely limited and dependent on legislative cooperation. As the political scientist Maurice Duverger argued in 1980, the extraordinary power of the French presidency is not formally established in the Constitution. Without even a plurality supporting the government in the National Assembly, effective governance may well be impossible without the president attempting to rule through the use of emergency powers.

These strained constitutional conditions are not simply a product of recent events or of a political blunder by President Macron in calling early elections. Rather, France’s looming constitutional crisis reflects the culmination of a broader political crisis which has been building since before Macron’s election, in which the fragmentation of French society, mirrored in the the party system, has paralysed parliamentary government.

As de Gaulle himself argued in 1964, in times of crisis ‘the indivisible authority of the state is entrusted completely to the president by the people who elected him’. On this highly contentious interpretation, the president is the sole guardian and guarantor of the constitution, with a unique duty to keep the machine of government running when it breaks down. It is a fantasy to which the ever-monarchical Macron might well be tempted to succumb, but he should recognise that the precedents he sets will be remembered in 2027 when the occupant of the Elysée may be no friend of his liberal vision of France.