War is horrible and thus starting a war should be avoidable at all costs - it should be a last resort, but this recommendation applies to the politicians and country leaders.

For the trooper, it's entirely differnent - assuming that a war exists already, the choice is about which bodies get sent there, and not wasting your training is a reasonable argument. Once a war exists, joining it usually contributes to it's end; if the other things are somewhat comparable, a shorter war is less horrible to everybody (especially local civilians) than a prolonged war, and you get a shorter war by winning with an overwhelming force.