Traditionally, signals intelligence is neatly bifurcated into offense and defense: intercept adversaries’ communication technology and protect one’s own. In the modern era, however, there is great convergence in the technologies used by friendly nations and by hostile ones. I’ve tried to tackle some of this in a new paper, “Nobody But Us: The Rise and Fall of the Golden Age of Signals Intelligence.” It’s published as part of the Hoover Institution's Aegis Paper Series.
My animating idea is that signals intelligence agencies find themselves in a dilemma: they must penetrate the very same technologies that they also at times must protect. The United States perhaps feels this tension most acutely, for a variety of reasons. To resolve it, the United States and its partners have relied on an approach sometimes called Nobody But Us, or NOBUS: target communications mechanisms using unique methods accessible only to the United States. This approach, which calls for advanced methods, aims to protect communications from American adversaries, yet also ensure American access when needed.
But the NOBUS approach depends as well on a number of American advantages that are under serious threat. These advantages for a time enabled what many have called “the golden age of signals intelligence.” The decline of these advantages renews the tension between offense and defense once more. My paper examines how the NOBUS approach works, its limits, and the challenging matter of what comes next.