[datsci_est_2015]

Their argument is that, by definition, it can’t be a world war unless all economic surplus is dedicated to war purposes.

I tend to agree with both of you, and that by extension, we will never see another world war unless society as we know it collapses significantly.

[jbboehr]

I don't think you are using standard definitions.

> A world war is an international conflict that involves most or all of the world's major powers. > https://en.wikipedia.org/wiki/World_war

> Total war is a type of warfare that mobilizes the totality of national resources to sustain war production, blurring the line between military and civilian activities and legitimate attacks on civilian targets as part of a war without restriction as to the combatants, territory or objectives involved. > https://en.wikipedia.org/wiki/Total_war

It does so happen that the two world wars were also total wars.