Frankly NATO with it's very strongest member the USA did prove to be effective. Basically doing what it was supposed to do. Prevent/stop another war in Europe, i.e. WWIII.
Having served in the Regular Army, in 4 Infantry Bns, '79-'90. Being deployed to Panama, the ROK DMZ, and even briefly to "West" Germany. It may have been "unpleasant" at times. But we were all volunteers. And we had a job to do.
However, the balance of power/MAD, etc., did lend itself to some level of "stability" to the post WWII world. Even though a number of smaller wars and conflicts occurred thru out the planet. It was not the massive loss of blood & treasure of both world wars. But sadly many still died. Albeit at in much smaller numbers. Which of course was/is of little comfort for the families of those who died.
However, IMO, the Russian loss in A'stan and the US's support of the Muj. Hastened the current era of instability in the world. With the rise of religious and ethic inspired terrorism, the so called "Arab Spring", etc.,etc.,. Which generally proved to be a very, very dark Fall, for many, IMO. As can clearly be seen in many in places in the 3d world as well as in certain locales in the West. Plus a massive refugee situation that has not been seen since WWII.
The instability incurred by ethic, religious, tribal, etc., differences and hatreds in many places of the 3d World. That resulted in the deaths of thousands upon thousands. Mostly at the hands of their fellow brothers, county men, etc. Is a black stain on humanity and does little to advance the human condition, etc.
Bottom line I think the US supported the wrong side in A'stan. Or at least not support the Muj at all. IIRC, the CIA's original plan was to let both/all side there "bleed" themselves out. But again, hindsight is 20/20. It appears that geopolitical error continues to be a problem. And will haunt many in the world for a long time …