OK before we move on to anything else.....really? I knew you didn't read those chapters I gave you, the military force are the shinobi, what in the world do you think they are fighting the war with, the Chunin exams is used to beef up each country's military force, that's why Konohamaru isn't in the war, because only Chunin and up are qualified to be in the military force and fight in the wars.
That is the same reason why there was peace
Tobirama TRIED to make peace but failed. The cloud betrayed everyone.
LOL ARE YOU SERIOUS(fyi: when I use caps in this case I am just laughing and yelling but not trying to insult you)
You say Hashirama is wrong for bothering the Tailed Beast but now you say Establishing the Military Force and forcing the Uchiha to play that role is okay? The Uchiha were not bothering anybody. They were forced to distanced themselves from the village and take a role in the leaf. Not to mention they were being watched.
Actually, yes it was the only reason and if not the only reason it was the main reason, ever great shinobi world war was over the tailed beast which if Hasirama would have just left them alone would never have happened, the tailed beast weren't even bothering anyone so he had no reason to go after them.
Also it's funny how you keep forgetting that Tobirama made peace with the cloud and established the military force.