I think a big difference is that asymmetry has grown a lot: The modern drone is much cheaper than any manned aircraft (while V1/V2 needed comparable or greater industrial input compared to fighter planes).
If you want to scramble manned fighters (even WW2-style ones!) every time cheap drones are launched then the pure material cost per intercept might be acceptable (no guarantee here: you need more fuel and your ammunition is potentially more expensive than the drones payload, too), but the pilot wage/training costs alone ruins your entire balance as soon as there is any risk of losing the interceptors (either from human error/crashes or the drone operator being sneaky).
Big problem with stationary AA is probably coverage (need too many sites) and flak artillery is not gonna work out like in the past because the drones can fly much lower and ruin your range that way.
The V2 was so expensive it was rather catastrophic to the German war budget. V1s, on the other hand, were very cheap to make and deploy.
> you need more fuel
Not much of a problem.
> and your ammunition is potentially more expensive than the drones payload
I'd say it's on par. A few rounds into a slow moving target moving in straight line would be easy to hit.
> the pilot wage/training costs alone ruins your entire balance as soon as there is any risk of losing the interceptors (either from human error/crashes or the drone operator being sneaky).
The US somehow managed to train an enormous number of competent pilots in WW2. I doubt there would be any shortage of men eager to fly them and "turkey shoot" the drones down. And there'd be a lot of mechanics falling all over themselves to build those machines!
A lot of people might find the idea fun, but actually sitting around in some remote base, just waiting for the next wave of drones to come? Even if you draft those people "for free", they could be working (or raise a family) instead, so the human cost is always there.
In WW2, the US lost ~15000 airmen just in training accidents to crew the ~300k planes it built. I'm sure we could get that rate down substantially with modern simulators and safety investments (=> also not free), but human lives simply got comparatively more expensive (and competent pilots were not that cheap back then either).
The attacker, meanwhile, is certainly gonna lose less men building and controlling the drones, and he can afford at least 10 attack drones for every interceptor you build.
If you did something like this on a larger scale, a big concern would also be that your manned interceptor aircraft simply become targets themselves, so the "low-risk turkey shooting" could quickly degrade.
I do expect (non-suicide?) interceptor drones as countermeasure at some point (specifically against the "cruise missile with props" style of attack drones, less so in the FPV weight class), and those could be conceptually quite similar to old prop fighters.
The marginal cost of a fighter aircraft to shoot down a drone flying slow in a straight line would be minimal, especially compared with the expense of each guided counter-rocket.
As for being targets themselves, the drones would be in enemy airspace so who/what is going to target the fighters?
I don't see how you realistically get airframe cost below $200k; you need basically a cropduster with a bunch of electronic equipment and weapon systems on top. That's worth 10 attack drones at least (realistically, US military would probably pay several times that).
> As for being targets themselves, the drones would be in enemy airspace so who/what is going to target the fighters?
Something like a sidewinder strapped under some of the attack drones. If you create the incentive (juicy, trained pilots exposed in slow aircraft engaging at low range) your opponent is gonna adapt. Exactly this evolution happened with Ukraine sea drones (already shot down several russian aircraft).
If you want to scramble manned fighters (even WW2-style ones!) every time cheap drones are launched then the pure material cost per intercept might be acceptable (no guarantee here: you need more fuel and your ammunition is potentially more expensive than the drones payload, too), but the pilot wage/training costs alone ruins your entire balance as soon as there is any risk of losing the interceptors (either from human error/crashes or the drone operator being sneaky).
Big problem with stationary AA is probably coverage (need too many sites) and flak artillery is not gonna work out like in the past because the drones can fly much lower and ruin your range that way.