revisionism

Advocacy of the revision of an accepted, usually long-standing view, theory, or doctrine, especially a revision of historical events and movements.

A recurrent tendency within the Communist movement to revise Marxist theory in such a way as to provide justification for a retreat from the revolutionary to the reformist position.

the advocacy of a revision of some accepted theory, doctrine or a view of historical events

an evolutionary form of Marxism, abandoning some of its original principles

a moderate evolutionary form of Marxism

any dangerous departure from the teachings of Marx