You don't have to fight if you disagree!
You talk it over, reach a comprimise.
Before the 20th century most wars were either religeous based or gains in territory. Not about disagreements. I've done my British history and we were the guys who had the largest empire since Rome which collapsed in 400AD and did all the invading in the last 300 years prior to 1914. Thats a fact. And it was about land and about money. If people disagreed we bought them out, thats how we got india and pakistan
. Be bought the Raj.