What you describe here is a full blown escalation that leads to the WW3 in the end. Of course there is diplomacy after the war is started and during the war. I

What you describe here is a full blown escalation that leads to the WW3 in the end. Of course there is diplomacy after the war is started and during the war. It’s the only way to achieve any peace barring a total defeat of one side, which didn’t happen in last 75 years. Heck, it was diplomacy that allowed US troops to pull out of Afghanistan orderly, without diplomacy there would be a bunch of dead soldiers.