Siam goes quickly Red, USSR goes stupid

[donagel]

In the last three games as Japan, I have justified a war goal against an unaligned, neutral Siam. I declare war. A day or 2 later I get "Siam has joined Commitern", quickly followed by DoW from Russia and allies.
Two issues:
1)Not understanding how Siam can go from unalign to Commiterrm so quickly.
2) USSR logic is off. Germany has just declared war on USSR. In this game, Russia has backed off from conflict and has demilitarized the border. (though they did recently cancel our non-agression pact for unknown reasons). Why would Russia rush to the into a 2 front war for SIAM who is going to fall in a week.

Have a savegame if you like.

 

[Tehrozer]

It just no sanity checks for ai and no logic for them they would join war against whole world just for one province bcs they need to in historical game and if its ahictorical then things happen and Ai always says yes at least in important things so it jut a chain reaction we need to wait for those some more