I was wondering how Trotsky came up with such a cool line, but he didn’t.

The original quite is: «Не каждый обезумевший мелкий бюргер может стать Гитлером, но во всяком неистовом лавочнике есть что-то от Гитлера.»

Which was translated as “Not every exasperated petty bourgeois could have become Hitler, but a particle of Hitler is lodged in every exasperated petty bourgeois.”

But in actuality, it means following: “Not every crazed petty bourgeois can become a Hitler, but every frenzied storekeeper has something of a Hitler in him.”

Source: I’m a native speaker