[dgoldstein0]

yup, I suspected you might mean something like that. Also of note, part of the major usefulness of tanks was to pair radios with them, so the new faster armies could coordinate as they moved.

And fun historical note, France definitely didn't get the memo, and were caught totally surprised by the speed of the Nazi assault. They were still using fixed phone and telegraph lines and their top commander wasn't even sitting by the phone. Their complete lack of imagination for how all the new technologies would change war was the main reason they blundered their defense so badly. Greatest victory the Nazi armies every won.