As regards the political assessment of the act, we maintain, of course, our old conviction, confirmed by decades of experience, that individual terrorist acts are inexpedient methods of political struggle.
“Killing is no murder,”[1] wrote our old Iskra about terrorist acts; we are not at all opposed to political killing (in this sense the servile writings of the opportunists in Vorwärts and the Vienna Arbeiter Zeitung are simply revolting), but as revolutionary tactics individual attacks are inexpedient and harmful. Only the mass movement can be considered genuine political struggle. Only in direct, immediate connection with the mass movement can and must individual terrorist acts be of value. In Russia the terrorists (against whom we always struggled) carried out a number of individual attacks; but in December 1905, when matters at last reached the stage of a mass movement, insurrection— when it was necessary to help the masses to use violence— then just at that moment the “terrorists” were missing. That is where the terrorists make their mistake.
Adler would have been of much greater help to the revolutionary movement if, without being afraid of a split, he had systematically gone over to illegal propaganda and agitation. It would be very good if some Left group were found to publish a leaflet in Vienna which would inform the workers of its view; if it branded in the sharpest possible way the servile behaviour of the Vienna Arbeiter Zeitung and Vorwärts, morally justified Adler’s act (“ killing is no murder”), but as a lesson for the workers declared: not terrorism but systematic, prolonged, self-sacrificing activity in revolutionary propaganda and agitation, demonstrations, etc., etc., against the lackey-like opportunist party, against, the imperialists, against one’s own governments, against the war that is what is needed.
Tell us also, please, how right it would be to regard Adler’s act as a gesture of despair? I think that politically it is so. He had lost his faith in the party, he could not bear the fact that it was impossible to work with this party, that it was impossible to work with Victor Adler, he could not accept the idea of a split and take upon himself the burdensome task of a struggle against the party. And as a result of his despair came this attempt.
An act of despair of a Kautskian (Volksrecht writes that Adler was not a supporter of the Zimmerwald Left, but rather a Kautskian).
But we revolutionaries cannot fall into despair. We are not afraid of a split. On the contrary, we recognise the necessity of a split, we explain to the masses why a split is inevitable and necessary, we call for work against the old party and for revolutionary mass struggle.
marxists.org/archive/lenin/works/1916/oct/25fk.htm