Comment by krisoft

> They knew about the devices in 1985, a few years after construction started in 1979 and construction didn't finish till 2000.

That happened due to the bugs found. This is the point I'm making. If your goal was to keep them where they were already are (Mokhovaya House) then the bag full of diodes mixed into the concrete did that perfectly for like 15ish years.

> They probably knew earlier than 1985.

Doesn't change that argument.

> So it probably wasn't a big deal and would've cost the SU a lot and they were less able to afford it.

We are talking about a few bags of diodes vs rebuilding three stories of the building with imported workers. This was a very cost efficient attack.