As head of the French Forces of the Interior of Eure-et-Loir, he took part in the liberation of Chartres where he greeted General Charles de Gaulle on the cathedral's forecourt.
But those failed, and as he was torn apart after breaking his relationship with the actor Silvia Monfort, Clavel accepted a professor tenure in the Carnot high school in Dijon.
Protesting, among other things, against the invasion of Hungary by Soviet tanks in 1956, and the use of torture in Algeria, he got involved with left-wing Gaullists in the Democratic Union of Labour in 1959.
First, he regained faith in the Catholic religion, a conversion triggered by his reading of a book by Paul Cochois about Pierre de Bérulle, the founder of the Oratorians congregation.
In an op-ed published in Le Monde on 15 June 1966, he sanctioned his breaking with the General while announcing to the press his availability to follow the Ben Barka trial as a judicial commentator.
The following year he contributed to the newspaper's TV column while he continued writing in Combat, and publishing novels such as La Pourpre de Judée (The Crimson of Judea) or Les Délices du genre humain (The Delights of Mankind, 1967).
[2] Perceiving the events of May as a "uprise of life" from a youth weary of consumption society, he found the revolutionary unrest similar to a party and even wished to lead the demonstrators on 13 May to assault the Élysée Palace.