Going to war is a complicated issue and is never completely justified not completely not justified for all the people of the country as there are multiple variables at play.
The absolute bloodbath of the second and first world war was considered justified by many even though it changed little in terms of the over all make up of the European societies except for the end of empires by the end of first world war.
It is often important to calculate if going to war is worth the damage it does and then the profit it pays off which is often a question of ideology.
