ACTUALLY, THAT ASSASSINATION WAS THE EXCUSE THE GERMANS WERE WAITING FOR, BROTHER! IT LED DIRECTLY TO STARTING THE WAR, DUDE!
War was on the mind of many of the powers. There could have been peace talks and negotiations in the process but many wanted to reclaim and claim themselves as Superpowers. They needed a excuse to go in.
It wasn't just about Germany's excuse who enhanced their Military budget in 1912 but France wanted revenge for Sedan.