On Thursday, November 16, 2017 at 1:55:43 AM UTC-5, wrote:
From 1969 to at least 1994, the US Embassy in Russia had listening devices (in-depth).

There have always been listening devices and there always will be.

I remember reading the clever way the Russians were snooping on the Americans with no bugs within half a mile of the room: they targeted a laser on a window pane of the room they were spying on. The window pane acted like a microphone diaphragm. They then demodulated the return signal which had the room audio modulated on it. Probably not hifi but I'll bet it was usable.

Gotta give them props for that trick.