It takes a profoundly ignorant view of historical facts to blame Stalin and Trotsky on foreign interference.
The mere presence of the Bolsheviks as a dominant force was due to foreign interference, as the Germans installed him and his friends in an attempt to destabilize the Russian Empire.
Trotsky's growth in authoritarianism, when he was previously a moderating force, started with the opportunistic German attacks at the fleets of the Red Army, and of course his rise to power from a middling figure to a preeminent Bolshevik was only made possible by German incitement of the Bolshevik movement to begin with.
Even Stalin's justification for power was based on (justified) appeals to centrally planned heavy industries, whose main motivation was military power which was necessary to to threats of invasion.
It is clear to anyone that both Stalin and Trotsky would have had much, much less power if they weren't able to justify centralization on the necessity to resist foreign agression, beyond that the consolidation of the Bolsheviks to begin with was a German plot.
You cannot just sweep across decades of internal Russian conflict and paint it with such a broad and quite frankly misinformed brush. Every European nation was involved to some extent, but none had the influence you claim nor did any create any of the central characters in this story.
The phenomena of revolutions turning authoritarian because of an outside enemy attempting to destabilize is in no way unique to the USSR. It's a pattern you see all across the world. It's what gets a movement that was opposed to even the concept of a standing army because of the centralization of power and the risk that brings to the largest standing army.
The Germans didn't create Lenin, but they fundamentally changed the course of the Rebellion against the Tsar by sending him back to Russia at that precise time. They had an intent in doing so that was realized.