The two miles long part is pretty easy to hit. The 150 feet wide part is less so.
If the target airfield is used by fighter type aircraft they only really need 50 to 75 feet of surviving width as long as it’s mostly straight. Which is to say a successful attacker would need to target each side separately and would need a 10m CEP to be able to reliably hit the left or right side on purpose.
Bridges, causeways, railways, and highways have the same problems as target sets. Real long but real thin. As you know well, impact footprints aren’t actually circular despite the C in CEP. Aligning the long axis of the weapon’s error ellipse with the long axis of the target is useful when the attacker can do it. Often geometry works against them.
Overall I agree with your various points upthread. An ICBM carrying a rock or a conventional warhead is dumb bordering on silly.
Seems to be a very expensive way to launch solid shot, basically cannonballs. Why do I suspect that the above was motivated more by “we have all these expensive missiles to be retired after Arms Control Treaties, let’s find a use for them not involving giving them to NASA”, then practicality.
A noticeably smaller one, in fact. An object with zero kinetic energy when it is far away from the earth will impact the Earth’s service at approximately 11.2 km/s, the escape velocity. Asteroids are usually moving at a fair clip relative to the Sun before they get drawn into the Earth’s gravitational field, and so they impact the Earth at a speed well above escape velocity. ICBMs, on the other hand, are by definition moving slower than escape velocity.
If you can wreck the taxiways (which are much wider - in total - you’ll admit), or the aprons, or the hanger, maintenance, & fueling facilities… you’ve still reduced the airfield’s utility. And those are within the CEP - Hitting an airfield is not exactly a challenge. But modern tactical aircraft are often, as you note, capable of rough field performance, which is a large part of why the idea for hitting airfields was dropped.
Yup. Further reasons why it’s a dumb idea.
Most of those involve an air-breathing final delivery stage, which are more maneuverable, and thus more amenable to terminal guidance. Still an expensive idea, and really not practical.