Purpose of the MBT?

[Fuchs]

Tukhachevskii, read my reply again with these quotes in mind:

Yep. All things it did in 1917 or 18. It's an infantry support weapon, and it has never progressed from being "a covered field gun," which is what it does best.

The tanks in WW2 were more capable, but there were few "new capabilities," bar the specialist engineer vehicles.

Sure, tanks of WW2 were technically very different, but when used correctly, they did things known to work in WW1. The Conceptual use stayed very coherent.

He completely downplays the difference between WWI and WWII tanks, apparently deliberately ignoring the differences in order to fit history to an idea.