It all depends on who's affected and what the extent of the damage would be to said countries.
A big war right now would throw a large portion of the world into shambles for a while, and the longer it goes on the significantly more damaging it will be. As long as the internet is operating, Bitcoin will be able to proliferate, but there are so many individual variables that can affect whether or not Bitcoin would be good that it's next to impossible to determine either way.
I agree to what have you said there sir, so many factors can be considered if at that time bitcoin is good as cash and internet is not affected by the calamity or any form of damage lets say internet is global that time bitcoin price will remain but it will be shaken to the parts of the world who is still relying on fiat