It’s easy for us to forget in all our ever-present over-interconnectedness that even as recent as 10 years ago, much less 30 years ago, letters were the primary means of communication, especially between radical leftist movements. And that the life of those underground radicals was lonely and anxious and ambiguous, especially as they wrestled with what is a justified use of lethal or symbolic violence, and that the solidarity they sought in their struggle would only be available from other radical groups, perhaps continents away.