Surveillance and the State

In the anthology “Activists and the Surveillance State”, Radha D’Souza writes in her essay “The Surveillance State: A Composition in Four Movements” that “Where there is State, there is Secrecy”.

I am inferring this statement to partly relate to the belief that the institution of the state is necessarily biased to protect the interests of capital and that, to protect capital, the state undertakes secret operations while displaying a facade of neutrality. D’Souza does not expand on this point, unfortunately. Is there any good reading that supports the latter understanding?