I mean, still what is significant? It seems you see the Napoleonic wars as such. Considering involvement of countries, the Crimean war had 4 great and 2 minor powers involved and lasted for 3 years. Granted the Crimean war was shorter and had less than the 6 great powers involved as were during the different coalition wars, with 1/4 the of the dead, but politically it was very significant and certainly not small nor regional in its effects.

That is factually incorrect, there have been many wars between the 1815 and 1914 that would qualify.

See the Crimean war 1853 or the German-French war 1870. With two or more great powers involved.

Or what is your definition?

That does not need to be the case (seeing that you probably meant this in jest, I still will take it on). Assuming the cat is already a higher dimensional being, which I feel is valid as it can move between them.

Imagine a Cube going through a 2D plane. You would see a cross section of the cube depending on the angle it goes through. The same would be the case for a hypercube in 4D and 3D (different effect as different cross section though).

So I would argue the comic is correct.