How about limited political pluralism?

How is a two party system where both parties are firmly pro-capitalism any different from a single party system with internal political currents?

Wanna talk about how prominent is the role of intelligence services and how much power do they have compared to the elected political representatives?

That's a better argument :) I'd also like to add that prisoners in the USA lose their voting rights. However, the argument was initially about Taiwan, not about the USA.