I guess there's not that much that's not "world" about it now, other than the region where most of the fighting is ... the image that went around of European refugees flooding onto a boat going in the other direction from Europe to Nth Africa during WW2 was pretty poignant.
Most people in the west tend to think of WW2 as starting simply when Germany invaded Poland in 1939... but why not when Japan invaded China in 1937 or even Manchuria in 1931? Or Italy/Ethiopia 1935? (The European civil war theory is kind of interesting: https://en.wikipedia.org/wiki/European_Civil_War ).
Growing up in the "cold war" we grew up thinking of a WW3 being an all out nuclear war with a 3 minute warning, but what they call WW2 gradually started to spread in Europe and Asia in the 1930s, similar to what's happened in the Middle East, Nth Africa and Central Asia over the last decade....
In a way the whole "world war" concept is kind of arbitrary... it never really stops, it just varies in intensity and region. Likewise, the "cold war" concept is a bit misleading - Korea, Vietnam and the Soviet-Afghanistan wars were all proxy "hot" wars between the US, USSR, (and China) — they couldn't go directly head to head without going nuclear, so they did it covertly, just like they're doing now. Millions still died and were displaced.
The M.A.D. doctrine is still there... the US and Russia have had a lot of practice at fighting over resources indirectly and covertly without going head to head.....
