In the aftermath of the split, Cannon elaborated on the essential issues of principle that had emerged. He stressed the irreconcilable opposition of Marxism to the spontaneist conceptions of Pablo and Mandel:
...We alone are unconditional adherents of the Lenin-Trotsky theory of the party of the conscious vanguard and its role as leader of the revolutionary struggle. This theory acquires burning actuality and dominates all others in the present epoch.
The problem of leadership now is not limited to spontaneous manifestations of the class struggle in a long drawn-out process, nor even to the conquest of power in this or that country where capitalism is especially weak. It is a question of the development of the international revolution and the socialist transformation of society. To admit that this can happen automatically is, in effect, to abandon Marxism altogether. No, it can only be a conscious operation, and it imperatively requires the leadership of the Marxist party which represents the conscious element in the historic process. No other party will do. No other tendency in the labor movement can be recognized as a satisfactory substitute. For that reason, our attitude towards all other parties and tendencies is irreconcilably hostile.
If the relation of forces requires the adaptation of the cadres of the vanguard to organizations dominated at the moment by such hostile tendencies—Stalinist, Social-Democratic, centrist—then such adaptation must be regarded at all times as a tactical adaptation, to facilitate the struggle against them; never to effect a reconciliation with them; never to ascribe to them the decisive historical role, with the Marxists assigned to the minor chore of giving friendly advice and “loyal” criticism...
Letter from Cannon to George Breitman, March 1, 1954, in Trotskyism Versus Revisionism, Volume Two (London: New Park, 1974) p. 65.