Left-interventionism (in Italian:
interventismo di sinistra) originated from a process of internal self-criticism carried out by a substantial part of the revolutionary
syndicalist movement, which, after the failure of
Red Week in June 1914, gave rise to a theoretical evolution of its thinking. In the following weeks,
Alceste De Ambris declared himself in favour of Italy's entry into the Great War alongside France, a fact that cost him his expulsion from the
anarcho-syndicalist trade union
Unione Sindacale Italiana (USI). This led first to the simultaneous voluntary expulsion from the USI, headed by , a neutralist and internationalist
anarchist, of the strong Milanese section, led by
Filippo Corridoni, and then to the expulsion of all interventionist sections. These went on to join with
Futurist interventionism, which was already creating unrest in the squares with
Filippo Tommaso Marinetti and
Umberto Boccioni. with
Benito Mussolini during a 1915 interventionist demonstration in
Milan On 18 October 1914,
Benito Mussolini, editor of the PSI's official newspaper
Avanti! "Foirward!) and until then a supporter of Italian neutrality as per party directives, published an article on the third page, in which he argued that maintaining the
neutral country line would have ghettoized the movement, relegating it to a subordinate position. He proposed arming the people for war; once it was over, they would be turning against the structures of the liberal and bourgeois state, giving rise to a revolution and the triumph of socialism. This cost Mussolini his removal from the newspaper on 20 October 1914, also the date in which the PSI published a manifesto in which it was reiterated its opposition to the conflict, and a few weeks later, on 8 November 1914, the same party reunited in
Bologna to unanimously express the position of incompatibility between socialism and war. On 15 November 1914, less than a month after his removal from the party's newspaper, Mussolini came out with the first copy of a new newspaper he founded, ''
Il Popolo d'Italia ("The People of Italy"), with a strongly interventionist line that earned for himself on 29 November 1914 the expulsion from the PSI because of his provocations against his comrades. On 14 November 1914, in an article entitled "Audacia''" ("Audacity"), in the columns of the new newspaper, he had written: "Today — I shout it out loud — anti-war propaganda is the propaganda of cowardice. It has luck because it tickles and exasperates the instinct of individual self-preservation. But for that very reason it is anti-revolutionary propaganda ... And as we resume the march it is up to you, young people of Italy; young people from factories and universities; young in years and young in spirit; young people who belong to the generation to which destiny has committed to make history; it is to you that I launch my cry of good wishes, sure that it will have in your ranks a vast resonance of echoes and sympathies ... 'War'." Under the influence of Mussolini and
Gaetano Salvemini, the then PSI member and university student
Antonio Gramsci wrote an article in the socialist weekly of Turin,
Il Grido del Popolo ("The Cry of the People"), that was published on 31 October 1914 and entitled "
Neutralità attiva e operante" ("Active and Operating Neutrality"), with which he would deviate from the official party line and split the ranks of the young Turin socialists. Gramsci's fellow Turinese socialist
Palmiro Togliatti volunteered in the
Royal Italian Army. The socialists Salvemini,
Leonida Bissolati, and
Carlo Rosselli were the voices of the front defined as democratic interventionism; they advocated a democratic alliance between Italy and the populations oppressed by the
Austro-Hungarian Empire for reciprocal liberation. Salvemini thought that "Germany's victory over France would be considered as proof of the incapacity of democracy to live freely alongside authoritarian political regimes, and would unleash the damage and shame of a long anti-democratic reaction on all of Europe."
Irredentism and the ideals of the
Risorgimento expanded in the pages of Salvemini in the columns of ''
("The Unity"), until they coincided with the defense of democratic civilization as opposed to the authoritarian culture personified by the Central Powers. Similar arguments united the socialist brothers and Rodolfo Mondolfo to the interventionist democratic front. In line with his personal views, the young Nenni volunteered and a commemorative photograph of him was reported in Il Popolo d'Italia''. In his work about Nenni's life, saw 24 November 1914, the date of his expulsion from the PSI's Milanese section "for political and moral unworthiness", as the death of Mussolini as a socialist left-interventionist and the beginning of a process that would see him leading the Italian fascist movement. Later in December, Mussolini published an article entitled "
Trincerocrazia" ("Trenchcracy"), in which he reclaimed for the veterans of the trenches the right to govern post-war Italy and prefigured the combatants of the Great War as the aristocracy of tomorrow and the central nucleus of a new ruling class. Mussolini's former PSI party members saw him as a traitor who sold out to capitalism for personal ambition. == Within the broad interventionist movement ==