Because as capitalist states struggle to maintain profits and control through soft means, the only other option is through direct control and violence. As the state gets more and more cozy with corporate and moneyed interests, and starts lashing out at the usual scape goats (trans/queer, communists, socialists, trade unionists, immigrants), we have what we call fascism.

Its the predictable end to a profit driven system that requires infinite growth to continue its existence.