Why War?

why have all this conflict? why can't people just understand that everyone has different opinions? no one needs to attack anyone. really, it pushes the people you are trying to change further away. just respect others and let them be. life is variable. there is no prescribed manner by which to go about it. the sooner we understand this, the more quickly we will be able to understand the freedom of choice, leading to the acceptance of decisions made by others. no wars involved.