What determines AI's chance to actually declare war?

[Culture Bomb]

I don't mean how do they decide when to start plotting war (WHEOOHRN,) but once they are plotting, how do they decide when to declare war?

I have seen the red fist go up and stay like that for pretty much the entire game without the war actually starting, so was wondering what factors influence how long they spend preparing for war.

Could it be related to the power of the potential target - ie if the target is too powerful they keep building more units but never 'think' they are powerful enough to attack?

 

[Ghpstage]

It has naught to do with the power of their intended target. Quote below is taken from the grandaddy of all AI DoW decision threads, its about an ALC game where an AI that went WHEOOHRN unexpectadly cancelled its war plans, it gives some insight into the behind the scenes areas of WHEOOHRN.

Sissy Sal:
Saladin has discarded his war plans (out of WHEOOH again) because he has assessed his offensive power not high enough after the (fixed!) turns of preparation.
If I understand it correctly the game mechanics for this assessment are rather funny as they only let Sal consider his offensive task force (= number of units with AI ATTACK, ATTACK_CITY and PILLAGE) in relation to the number and size of his cities. In contrast to his decision to start preparing for a war, this judgement is completely independent of your power and the strength of the units he has, so upgrading his Camels and Jumbos didn't help either. As part of his personality he also favors to build units with (the wrong) UNITAI_COUNTER (XML-value UnitAIWeightModifier) during times of peace. Together with his protective trait this turns him more into a strong defender than a real threatening offensive aggressor (compare to Monty!).