Why do conservatives consider communism and fascism to be close cousins and the opposite of conservatism?
More Like Siblings
Quora has a page with some wonderful answers that describe common characteristics of Communism and Fascism and that contrast them with Conservatism. However, common characteristics merely makes for similarity. “Close cousins” implies common heritage and genetic commonality that cause the commonalities. The metaphor bears truth.
Just as Vladimir Lenin and built Mao Zedong built their bloody Communist regimes upon a foundation of Marxism, so did Giovanni Gentile built his philosophy of Fascism upon Marxism. (Is Fascism Right or Left?) Thus, Communism and Fascism derive from a common philosophy. They are more like half-sibling rivals than like cousins. (Progressivism shares those roots, and Communist governments had a hand in establishing it in American politics.)
Children of Marxism
The children of Marxism are rooted in the idea that the collective (that is, in practice, the State) is a higher organism than man. They require acceptance of a Utopian notion of citizens submitting their interests to the common good.
That is a fine idea, as long as the system is filled with hypothetical, ideal humans. However, in practice, it has two fatal flaws. First, humans are a competitive, self-interested species. Someone will always claw his or her way to the top, and bolder citizens will fight for freedom.
Second, the State will always have to use indoctrination, intimidation, and force to cause everybody to submit to the collective’s will or to preserve the top dog’s rule, crushing freedom and removing incentive to excel. Thus, Marxism’s children, Communism and Fascism, always lead to totalitarianism.
Conservatism
American Conservatism is rooted in the idea that the individual is the ultimate earthly organism. That is why the Founders established a government with the People at the top, a Constitution expressing their will, and Government at the bottom. Whereas the People subjected under Marxism exist to serve the government, in Conservatism, the government exists to serve the people. That is why Marxist governments claim for themselves all capital, or at least control of capital, whereas Capitalist governments remove as little capital as possible from the People.
Conservatism also recognizes what happens when you introduce flawed, self-interested humans into any system. Freedom and retaining the fruit of one’s labors give people incentive to excel, raising metrics for the whole society. Moreover, Conservatism recognizes the need for balancing powers within politics and government, a major tenet of the US Constitution, so that competing interests keep each other in check. This contrasts against rule one-party rule and dictatorship that always develop in Marxist governments.
Another contrast is that Marxist “Social Justice” dictates equality of outcome that places heavier burdens on disfavored classes, such as forced redistribution of wealth to less successful classes, whereas Conservatism emphasizes equality of rights, individual responsibility for outcome, and voluntary charity. Thus, Conservatism champions personal charity and individual justice whereas Social Justice depersonalizes charity and undermines equal justice.
I have specified American Conservatism because the word Conservatism is defined by its context. It generally indicates a philosophy of preserving the current system. American Conservatives who want to restore lost values are insultingly called "paleo conservatives," when in fact, many of them would have been considered moderate-to-liberal just a generation ago.
American Conservatism is known in the rest of the world as liberalism because it champions conditions that allow liberty, unlike monarchy and Marxism. More importantly, American Conservatism could be better described as Americanism because it promotes the foundational values of American society and government, in resistance to Marxist values that now dominate the Left.
However, we stick with the label Conservatism because we can’t stomach the screams of “How dare you call me un-American” from un-American Leftists.