Good lessons. Like ignoring previous military plans that showed how tough a nut Iran would be to crack.
Lessons like the value of AWACs. Now we're down to 15 and the availability rate is like 50%. So 8 or so WORLDWIDE. Yeah, that's a good lesson. And we've cancelled its replacement after someone (probably Elon) whispered BS into Trump's ear about space based sensors.
I'm sure China is watching with a notepad out about all these lessons. Thucydides is rolling in his grave.