What u/klingma is saying is that WW1 and WW2 was essentially one war - The Great European Civil War.

Many historians agree.

The Pacific War and the Rise of Japan was caused by the threat of European Nations to Japan and Japan's desire to not be minimalized and thinking they too deserved a Colonial Empire.

WW1, Russo-Polish War, conflicts in Balkans, Russian Civil War, internal revolutions, The Russo-Finnish conflict, the Sino-Japanese conflicts, Kalkhin-Gol; the list goes on.

The 1914 to 1945 war had an interruption in Western Europe with an Armistice. A pause in one sector.

Maximum Violence ended it again in Japan and The West and still other conflicts went on.

The USSR invasions of Warsaw Pact nations post 1945 can be considered more of the same. Korean War and Vietnam war were responses to the historical forces of WW2.