Robert Paxton (author of Anatomy of Fascism) points out that one feature of fascism is it's flexibility with doctirine and truth. It provides raw emotion and sensual experience.
>Fascism rested not upon the truth of its doctrine but upon the leader's mystical union with historic destiny of his people. The fascist leader wanted to bring his people into a higher realm of politics that they would experience sensually: the warmth of belonging to a race now fully aware of its identity, historic destiny, and power; the excitement of participating in a vast collective enterprise; the gratification of submerging oneself in a wave of shared feelings, and of sacrificing one's petty concerns for the group's good; and the thrill of domination. Fascism deliberate replacement of reasoned debate with immediate sensual experience transformed politics, as the exiled cultural critic Walter Benjamin was first to point, into aesthetics. And the ultimate fascist aesthetic experience, Benjamin warned in 1936, was war.
>Fascist leaders made no secret of having no program. Fascism radical instrumentalization of truth explains why fascists never bothered to write any casuistical literature when they changed their program as they did often and without compunction. Stalin was forever writing to prove that his policies accorded somehow with the principles of Marx and Lenin; Hitler and Mussolini never bothered with any such theoretical justification.
Paxtons short definition is pretty good:
a form of political behavior marked by obsessive preoccupation with community decline, humiliation, or victim-hood and by compensatory cults of unity, energy, and purity, in which a mass-based party of committed nationalist militants, working in uneasy but effective collaboration with traditional elites, abandons democratic liberties and pursues with redemptive violence and without ethical or legal restraints goals of internal cleansing and external expansion.