In the UK they did a sort of ‘What if’ scenario film. They took a gradual build up conflict based on events in Ukraine (pro russian seperatists leading to confirmed Russian involvment in one of the Baltic countries that was part of NATO).
The ‘players’ were former leaders of the British Cabinet and Military who would have had to make the desicions leading to war and just what the response would be.
World War Three: Inside the War Room
The final parts of the escalation to total war were the Russians had just nuked a British Carrier - should the British respond as required by the NATO treaty and the limited response idea.
The vote came down to - No - it was not worth going to total war or even escalating the conflict by sending in more than advisers just for a couple of million people. Which was tantamount to saying NATO would break up and be powerless when faced with a real equal challenge.
Ok it was former players with hindsight and their safe future to look forward to rather than actually on the edge of their seats real lives involved, but it did give an idea of the mindset and a likely result of a vote to go nuclear (always assuming it was a slow build up and not a major first strike scenario)