Corners were cut. And knowing what corners could be cut was important. You probably had to be on the ground making decisions to know what was needed. But that's still getting into strategy over technology. I mean in Afghanistan a bunch of goat farmers with no technology defeated the American military. The Taliban with the best technology were the ones easiest to kill.
Discussion
That's something a bit different than WW3. Afghanistan's Taliban held off the US because the nature of that war. Kind of like Vietnam. When invading a smaller country, the invaded have more to lose, and guerrilla warfare can work.
There hasn't been a world war since the nuclear weapon was invented. I believe nuclear war is why we now see small proxy wars between the nuclear powers in country's that don't have access to those weapons. The closest that I know of is the skirmishes between India and China. But those battles only have minor casualties and end within a day or two.
The world may become more peaceful as every country gets nukes. WWIII seems far fetched.