Complex sentence: The Anti-Germans presume that any global transformation to communism only can happen with and not against the de facto forces of the Enlightenment, and reject Antiimperialism, which they see as the current mainstream inside Marxism.
Split into simpler sentences: The Anti-Germans presume that any global transformation to communism can only happen with and not against the de-facto forces of the Enlightenment. Thus they reject Anti-imperialism, which they see as the current mainstream inside Marxism.