To some extent I think you can do most of that on Lemmy.

You can upload images for your posts (not sure for short videos) and cross-post them to other communities.

Edit: I don’t know kbin.social but I suspect it would be more adequate to what you want to do.

Out of curiosity, you say an overwhelming conventional force. Does that mean the NATO plan explicitly says it should be conventional?

I always imagined that if a country nukes another they would immediately be nuked themselves. Because if a country is using their nuclear arsenal, it’s probably a bit late to moves armies around.