In order to find other arguments against Stalinism than his personal dislike for a competitor in intra-party struggles, Trotsky must discover and construct political differences between himself and Stalin, and between Stalin and Lenin in order to support his assertion that without Stalin things would have been different in Russia and elsewhere.
There could not have been any ‘theoretic’ differences between Lenin and Stalin, as the only theoretical work bearing the name of the latter had been inspired and supervised by Lenin. And if Stalin’s ‘nature craved’ the centralised party machine, it was Lenin who constructed the perfect machine for him, so that on that score, too, no differences could arise. In fact, as long as Lenin was active, Stalin was no trouble to him, however troublesome he may have been to ‘The Number Two Bolshevik’.
Still, in order for Trotsky to explain the ‘Soviet Thermidor’, there must be a difference between Leninism and Stalinism, provided, of course, there was such a Thermidor. On this point, Trotsky has brought forth various ideas as to when it took place, but in his Stalin biography he ignores the question of time in favour of the simple statement that it had something to do with the “increasing privileges for the bureaucracy”. However, this only brings us back to the early period of the Bolshevik dictatorship which found Lenin and Trotsky engaged in creating the state bureaucracy and increasing its efficiency by increasing its privileges.