If you can sell a religion, you can sell a war.
Conflict (war/disagreement) is a product of uncompromising beliefs and the drive for self preservation. People maintain beliefs that serve as a utility for self preservation (however they define it). Problem is, most beliefs are inherited unquestionably. Religion is just one belief system that masquerades as being immutably true (One may say Science is another). So long as people see things as being absolutely true and false rather than contextually contingent on social norms and subjective interests, we’re gonna have trouble avoiding conflict and arriving at agreements that jive with our experience. There is no transcendent ‘right’ and ‘wrong’. There’s only what’s best for ‘me’ or ‘us’. It all serves some interest. It just depends on whose. That’s why dialog is so important.