In practice by the time a frontline S-400 knows that there is something there, supersonic jets at cruising altitude already have too much kinetic energy to intercept. It doesn't matter if an anti-aircraft missile is capable of mach 14 if it's got less than the radar horizon worth of distance to accelerate and catch the target. A full AA system depends on a massive early warning radar system to launch interceptors and AA missiles, one that will quickly get destroyed by RF missiles in a real engagement.

MANPADs like the FIM-92 have an effective firing range that is a small fraction of the flight ceiling of jets, regardless of the missile's max velocity. They're not a threat unless a jet is flying very low for close air support or when lacking precision munitions, and the operator gets very lucky.

The reason I mention MANPADs is because of the target domain after air superiority is achieved. For instance helicopters have been used extensively in US invasions in the Mideast thanks to sustained air superiority. That quickly goes out of the picture when there's MANPADs everywhere. Even in the Israeli conflict, which is extremely asymmetric, helicopters have proven highly vulnerable.

As for the numbers stuff, all modern air defense systems have independent integrated radar of at least their engagement range, and do not rely on external radar systems, though of course everything works much better with layering and cooperation. An F35 at max speed (which it is only capable of reach at high altitude for very brief periods of time) is hitting about 1975 km/h. An S-400's engagement and radar range is about 400km. That's an engagement radius of more than 12 minutes at max speed. The engagement window would be smaller with a low & slow approach, but then you start running into various other risks, even going back to MANPADs.

One could try a long-range stand-off but that's unlikely to prove effective without getting into the primary way to disable anti-air defenses - overwhelm them. But that's extremely non-trivial even if the systems are in relative isolation, let alone if they're part of a comprehensive anti-air system. And all of this for one system. Again I would appeal to Ukraine. Their anti-air defenses are relatively limited yet it's been more than enough to greatly limit the engagement capabilities of Russia's Su-57s.

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Actually I also completely failed to mention another major factor. If this sort of war breaks out, satellites are going boom shortly thereafter, the global internet would follow in short order. This will further reduce the chances of any sort of effective elimination of anti-air.

> In practice by the time a frontline S-400 knows that there is something there, supersonic jets at cruising altitude already have too much kinetic energy to intercept.

The Swedish air force could routinely (16% of the time) get a fighter jet based missile lock on a frigging SR-71 in the 80s! 40 years later, altitude and speed do not help as much as you think. And radars are networked.

https://en.wikipedia.org/wiki/Lockheed_SR-71_Blackbird

Getting a missile lock isn't the same as hitting it.

Citing the hard specification of various military hardware does not an analysis make. You neglected entirely the soft components, which is why we see severe under performance of the Russian air force in Ukraine.

It is unclear if the US will prevail against a peer adversary in an air war, but if anybody is able to achieve air supremacy, it would be the US and their allies.