I never considered this before because I always ignored air. Essentially I was playing a hopeless game. Persia essentially had a perpetual Golden Age and owned most of the world with an army of incredible size. I'm sitting on a dozen cities (over half of them are small cities which I am just using on distant islands to farm resources and generate some additional gold. and they have about 45, mostly all good cities. Seeing as how I was the only civ left with anything decent (they had either wiled out everyone else, or driven them to unimportant islands leaving them with 1-2 tiny cities). Anyway, they declare, and about a 2 dozen units pour over my borders. Effectively it's hopeless because their output is about 4X what mine is, and they are 12% more further ahead on the tech tree; and are allied with all of the city states except 1 which the Celts have (the celts are sitting on one city with a population on 5 up in the snow and tundra)
I have cash, so essentially I use it to buy a bunch of bombers. To make a long story short, 30-50 turns later, the Persian army is wiped out, I am marching into their capital. I only lost two units total (two expendable land ships which they bombed as I approached their capital)
In the entire conflict, despite their huge armies and superiority in every aspect, they were hopelessly outgunned. Essentially, by the end, I could hit them whenever I wanted with gigantic firepower. In my opinion, air strikes are supremely overpowered. Realistically, I should have lost my capital and essentially that war within 10 turns. It was just a matter of rush buying a bunch of planes in one city.
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