Russia has 1674 Nuclear weapons deployed,I'm not as confident as you seem to be that every single Russian Nuclear warhead would not fire if the button was pressed.
The longer the war goes on the more likely an accident or an escalation occurs.
I'm more worried about an accident that occurs because the two countries are at war with eachother, Ukraine as a proxy for the US.
Better the Europeans police the border between Russia and Ukraine after a settlement and the US and Russia not be in direct conflict with eachother. Also Ukraine is running out of people and recruiting older men and more women into the army, do you think that European troops should be enlisted to fight there until the origional border of Ukraine is returned? What is your end game scenario?
Some incidents have involved early warning sensors giving accurate but ambiguous data that suggested an attack: • January 25, 1995. A Russian early warning radar detected a missile launch off the coast of Norway with flight characteristics similar to those of a U.S. submarinelaunched ballistic missile. Fearing that it could be the first move in a larger attack, Russian nuclear forces quickly went on full alert. Russian President Boris Yeltsin activated his “nuclear football” and retrieved launch codes, preparing for a retaliatory launch. Fortunately, the tops of clouds had fooled the satellite into thinking it was detecting a missile attack.
Close Calls with Nuclear Weapons