Everyone in the military did indeed have their "doctrine and practice" in mind, the status quo, and suddenly the world rushed up to the military's front door, knocked furiously at the door saying "we need 20,000 Stingers, fast!" And hopefully they had the introspection to realize 'wow, we failed. We can't supply this. Our doctrine and tactics are wrong."
Do you seek air superiority via spending money to create an air-superior fighter jet, or do you seek air superiority via spending money to give every infantry soldier a manpad? Two different tactics with the same goal. Except that the former is a wasteful illusion of superiority, the latter is meat-and-potatoes common sense superiority.
Begs the question what's going on with the lack of common sense in the military.