Spanish Civil War and the 1940s
When the Spanish Civil War broke out in 1936, he was quick to support the Republican side
but within a year, after internal rifts in the Republican armed forces erupted into actual combat — the Stalinist Unified Socialist Party of Catalonia on one side, and the Trotskyist Workers' Party of Marxist Unification(POUM)
[the POUM was friendly toward Trotsky but he did not support it, and it is incorrect to call the POUM a Trotskyist party] and anarchist CNT on the other, he had lost a great deal of faith in the Soviet-supported factions.
In 1946, Guérin went to the United States, and was appalled at the treatment of African Americans, and their lack of equality with
their White counterparts. He witnessed the Civil Rights Movement, and chronicled his experience in his book Negroes On the March, an important text in the doctrine of revolutionary integrationism,
which argues that the struggle for equality by African Americans in the U.S. is their primary struggle, that it can be won only via the struggle by the entire working class for socialism, and that it is essential to that larger struggle. The same year he published his in-depth
study of the French Revolution, La lutte de classes sous la première République : Bourgeois et 'bras
nus' (1793-1797) ("Class struggle in the First Republic: Bourgeoisie and the people") in which, unlike many leftist historians,
he was very critical of the Jacobins.
1959, by publishing Youth of Libertarian Socialism he began his involvement with anarchism. Guérin belonged to several anarchist-communist organizations: the ORA (Anarchist Revolutionary Organization), from 1971 to 1977, the UTCL (Union of the Libertarian Communist Workers), from 1979 to his death in 1988 (in 1991, the UTCL became Alternative libertaire).
He also participated in the
events of May 1968 in Paris, as well as his calls for Algerian independence from France. Guérin's writings were prolific in France, but
English translations are rare. Guérin was the subject of the French film Daniel Guérin, Combats Dans le Siècle (1904-1988), made by Patrice Spadoni and Laurent
Mulheisen. In 1969 Guerin published an essay called "Libertarian Marxism?" in which he dealt with the debate between Karl Marx and Mikhail
Bakunin at the First International and afterwards he suggested that "Libertarian
marxism rejects determinism and fatalism, giving the greater place to individual will, intuition, imagination, reflex speeds, and to the deep instincts of the masses, which are more far-seeing in hours of crisis than the reasonings of the ‘elites’;
libertarian marxism thinks of the effects of surprise, provocation and boldness, refuses to be cluttered and paralysed by a heavy ‘scientific’ apparatus, doesn’t equivocate or bluff, and guards itself from adventurism as much as from fear
of the unknown."
The writings of the French bisexual anarchist Daniel Guérin offer an insight into the tension sexual minorities among the Left have often felt. He was a leading figure in the French Left from the 1930s until his death in 1988. He contributed to the homophile
journal Arcadie. In 1954, Guérin was widely attacked for his study of the Kinsey Reports in which he
also detailed the oppression of homosexuals in France. "The harshest [criticisms] came from Marxists, who tend seriously to underestimate the form of oppression which is antisexual terrorism. I expected it, of course, and I knew that in publishing my book
I was running the risk of being attacked by those to whom I feel closest on a political level." After coming out in 1965, Guérin
was abandoned by the Left, and his papers on sexual liberation were censored or refused publication in left-wing journals. Guérin was involved in the uprising of May 1968, and was a part of the French Gay Liberation movement that emerged after
the events. Decades later, Frédéric Martel described Guérin as the "grandfather of the French homosexual movement." Guérin spoke about the extreme hostility toward homosexuality that permeated the left throughout much of the
20th century. "Not so many years ago, to declare oneself a revolutionary and to confess to being homosexual were incompatible," Guérin wrote in 1975. Guerin saw homosexuality as a form of "class treason" like many contemporaries.