This article begins by recounting a series of mass surveillance practices conducted by members of the “Five Eyes” spying alliance. While boundary- and intersubjectivity-based theories of privacy register some of the harms linked to such practices I demonstrate how neither are holistically capable of registering these harms. Given these theories’ deficiencies I argue that critiques of signals intelligence surveillance practices can be better grounded on why the practices intrude on basic communicative rights, including those related to privacy. The crux of the argument is that pervasive mass surveillance erodes essential boundaries between public and private spheres by compromising populations’ abilities to freely communicate with one anot...