I have no time to listen to the podcast right now but based on the short summary, I've been thinking about this, too, since there has been much talk about the way this plays out for Russia might deter China from invading Taiwan. That basically implies Russia entered unknown territory by invading Ukraine since it is the first war in which modern military technology is used by attacker and defender alike, at least on a larger scale. Modern warfare might benefit defenders to a vastly greater degree than aggressors. I wasn't particularly interested in military stuff prior to this conflict so I don't know if that's been a theory before but if it was then chances are it's never been tested. It would generally be a very welcome development I suppose since it makes wars of conquest much less profitable for superior powers unless they use weaponry that go against there purposes (mass destruction that will spark fierce resistance, political isolation, domestic protests and on top leaves nothing to conquer).