Some people on here and social media need to chill out. Putin isn't starting WWIII over Syria.
That's not how WWIII (if it ever comes) will start.
Neither side wants WWIII, or would just "start" WWIII, over something like tonight.
A nuclear exchange comes after a slow but steady escalation of events from BOTH SIDES. One side starts something small, the other reacts, they each step-up confrontation and ultimately one side "freaks-out" and launches (causing the other to do the same).
The entire cascading of military events, leading up to Earth's destruction, could take place over a number of days or even weeks.
PS: I'm not saying it will take place. But let's not diminish that tonight's events could be the spark to something we all don't want to see.