Why are communist leaders called dictators?

Answer 1

Most Communist states do not degenerate into dictatorships, but they do degenerate into authoritarian regimes based on party-control over all aspects of the state and government.

This occurs because all Communist states have been thus far based on the political practice of Leninism and theories of Marxism-Leninism (aka, Stalinism).

Leninism is the view that a Vanguard party organized along paramilitary lines and comprised of "professional revolutionaries" is required in order to achieve a worker's revolution. After the revolution, this party would centralize all power in its hands for the purpose of leading the nation in the development of socialism.

The strategy of Leninism is based on the centralized Vanguard party and the idea of democratic centralism, which states that once the party makes decisions, those decisions cannot be questioned. This is done to make the party an efficient organization impervious to counter-revolutionary action.

Leninism and the political system of democratic centralism set the stage for authoritarianism and for the abuse of political power by the party-elite, because the party is given so much power and is not held accountable to any other public body.

Ultimately, it is antithetical to socialism and communism which require collective decision-making and widespread participation by all members of society. The logical outcome is authoritarian rule by the party (or in some cases, as during Stalin's and Mao's rule, by the leader of the Party).

Answer 2

because thay are just like dictator they fight for power