If you want to understand the threat of WW3 better, this video of a meeting of the International Peace Coalition by the Schiller Institute is very enlightening.

Among other things:
* Russia does not have launch detection satellites, they rely on ground radar to detect incoming ICBMs
* Taking out their strategic defense radar has shortened their decision making time, perhaps to the level that they will turn on an automated response (no human decision necessary)
* Politicians are almost completely focused on politics and don't know the technical details about what they are ordering.

https://www.youtube.com/watch?v=qrpXtDiJjgA