"I would still consider WWI the last hurrah of prestige wars (where an essentially divine monarch instigated war for personal reasons and had the authority to enforce his will over the entire nation)"
I agree to that, but I would add, that the monarch did not had to enforce their will on the nation. At least germany was very willing to go cheering into war. And I believe england, too and france (without a monarch), too.
In russia it was more enforced, but the tsar eventually lost his power and life over it.
It was a nationalistic war - each side fought for the glory and power of their nation (whether with a monarch, or not).
And maybe yes, the last big hurah war - where war was welcomed by the majority of the population.
WW2 had to be presented as neccessary and forced upon from the outside. Even in Nazi-germany. Some youth went into the fight eagerly, but most of the elder generations had way too many memories of the last one, which was not so glorious alltoghether.
(Oh and I certainly do not have a rose tinted view of pre WW1.)
