We spent a lot of blood and treasure helping Afghanistan attempt to enter the 21st century. I will not pass judgement on how successful we were because we did much good there. Militarily, I worry that we now have a couple of generations of soldiers who think that what they experienced during their tours there is the new baseline for warfare. It isn’t. Fighting insurgencies is older than the Roman Legions. War is experienced along a broad spectrum and our fight there was only one narrow slice of that spectrum. Our collective experience taught us much but we must learn to add to our collective knowledge and not replace what we knew with what we now know.
The use of tanks is an excellent case in point. How we employed armour assisting infantry fight insurgents does not mean that we now do not need to relearn how to employ armour in mass, in conventional battle. Look at the invasion of Ukraine. It looks more like 1942 than like 2002. Everything old is new again, as the saying goes.