You don't plan around what happened in the past. You learn lessons from it ( hopefully ).
In designing any new aircraft, you have to look at what it's adversaries might be.
And plan around that, the numbers likely to be deployed, logistical factors.
Factor in what has happened in the Ukraine, and how that could have gone.
If the Russians had decided to occupy, what would they have used, and what would the Ukrainians have wanted to oppose that ?
( modern aircraft, in part, strike for the Russians, air defense/air superiority for the Ukrainians )
There is conflict in Syria. My recollection is that Assad has been using aircraft on his people, and that is part of what keep him from being overthrown.
What did the Iraqis want from us when ISIS/ISIL/ started taking territory.
Aircraft. For us to use our aircraft to assist them in driving them out.
China is being increasingly belligerent ( I'm sure they see it as taking their place in the sun, but where have we heard that before ), especially in the South China Seas with Japan, the Philippians, and Vietnam ( at least )
( recent news includes the articles about the oil rigs China has placed near Vietnam, and the Naval issue that have proceeded.
They are attempting to jump start their military ( and commercial ) aircraft industry.
Conflict appears to be getting smaller. Yes. But the threat of conflict is still there. And the capability on the part of other nations is still there.
Imagine America destroys all it's aircraft, naval vessels and disbands the army after destroying all it's weapons.
What happens next?
I would predict that our borders with Canada and Mexico would change, at minimum.
I'm not sure if Russian or China have the logistical capability to move in such a scenario, but then, America's moves in Afghanistan surprised the snot out of me. ( not the absolute power, but the ability to project it so far away.
We cant disarm, as appealing as that sounds. We cant even stop looking at what comes next, as that becomes disarming, in effect, after a period of time.
Disclosure, I am fairly liberal, Christian, opposed to war, use too many parenthesis and commas.