4th generation aircraft are not sustainable in modern combat without a wide array of assistance from EW etc. The losses of aircraft in Ukraine on both sides are horrifying. The only reasons the Ukrainians persist is because they have no choice. The Russians can sit outside of the Ukrainian engagement range and lob semi-smart bombs, or air to air missiles at any Ukrainian aircraft that show up on their radar.
The real reason stealth is needed is as a counter to GBAD. Modern anti-aircraft missiles are incredible lethal.
"4th generation aircraft are not sustainable in modern combat without a wide array of assistance from EW etc. "
But isn't that true of the F35 as well?
On it's own, I doubt it would survive much longer on the eastern front in Ukraine.
In Iran the F-35 also did not fly around freely while the ground radars were active. They had to be taken out first. For that stealth was probably useful (and in general it is).
But it is not making them invisible - and cheap sensors and AI is likely to counter it soon. Because sensors and analysis will get better over time and sensors also better and cheaper. But the stealth will remain largely the same. It cannot really be upgraded for existing jets.
> cheap sensors and AI is likely to counter it soon.
The burning question is what decision would AI make in Pearl Harbor. Would it have said flock of birds? Would it be keying in on flocks of birds instead?
> "modern combat"
> have no choice
That's my point. Any battlefield today is "modern", but militaries operate with what they have. From Russia to the Houthis passing via the Houthis, we've seen insane amounts of damage done on "a modern battlefield" with anything from Cold War era equipment to cheap drones assembled by a terrorist group living in the mountains with no industrial base.
Yes, if the US wants to fight China, and vice versa, it needs 5th gen jets. Everyone else doesn't need them. They're nice to have to make your job easier (like Israel vs Iran), but don't guarantee you anything (like Israel vs Iran).