Food for thought, there is a 1998 German-British pseudo-documentary on the start of World War Three in 1990 with a lengthy prelude beginning in 1989. It's available in English on YouTube here:
https://www.youtube.com/watch?v=HZf-M_vC22w.
The German version, also on YT, and the English differ in various details explained on Wikipedia (here:
https://en.wikipedia.org/wiki/World_War_III_(film)), the article also gives a extensive summary.
I quite recommend that piece of fiction, the scenario is fictional, of course, but well researched and based on all plans and scenarios available back then to public research.