Quick, what's the radar cross section (RCS) of the B-2? Don't know? Of course not - that's one of the most closely guarded characteristics of the plane. How about the resistance to EMP effects? Nope, they won't tell you that either and for good reason. If a potential enemy knew those numbers, it'd be a lot easier to develop a countermeasure to defeat the plane. In effect, a leak or two could wipe out the billions spend on R&D to make the plane.

The pertinent data for the BMD tests is and should be classified and at the same time, it should be given to the appropriate members of Congress so they can exercise their oversight capability. That is happening. What the restrictions do is tell members of Congress that they can't leak that classified information to the public. Personally, I have no problem with that.

As for that MIT professor, he did detect a flaw in the Patriot PAC II fusing system that has since been fixed. Many of us who saw the news footage could tell that some of the warheads were not being destroyed in flight. However, his technique of using TV footage to analyze the intercepts is seriously flawed for a simple reason - the frame rate is far too low to accurately determine the relative positions of the two missiles. The NTSC TV standard calls for a frame rate of 30 fps. When you have two missiles closing on each other at several thousand MPH, the distance covered between frames is too great for an accurate positional assessment. That's why they use very high speed cameras (often several thousand frames per second) to record test intercepts so that the distance between frames is small enough to be accurately measured.

The fusing problem on the Patriot when used against the Scuds had a couple components. First, the Patriot was designed as an anti-aircraft missile, so it used a proximity warhead designed to detonate on impact or when the missile passes close to the target. When you have a missile like the Scud where the warhead and rocket body remain attached throughout the flight, you have to detonate the proximity warhead a few miliseconds early to destroy the warhead. The Patriots were detonating just a little too late for that. In essence, they were destroying the useless rocket body instead of the warhead. I remember several times seeing the Patriot detonations followed by the warhead detonating on ground impact. Like I said, that problem has been fixed. The other problem that the PAC II had was dealing with the Scuds when they broke up in flight. Saddam's people had modified the Scud to increase the range. This weakened the missile, frequently causing it to break up on descent (V-2s often did the same thing in WWII). The Patriot radar system had a hard time discriminating the warhead from the debris, making targeting difficult. I'm pretty sure that they've addressed this problem as well.

The new NMD interceptors use kinetic kill instead of a proximity warhead to destroy the target. This requires extremely high accuracy - something they seem to have developed. Either it hits the target or it doesn't, and that's immediately obvious.

The problem of discriminating the RV from decoys is fundamental to the NMD design. Most of the discrimination is performed by ground radars. This is nothing new. We were doing piece discrimination using the Cobra Dane radar when I was there in 1990 (and the radar had been doing it in the 1970s when the radar became operational) as part of post mission processing. We couldn't do it very well in real-time because the system was powered by an old Cyber computer with only 512 KB of RAM and the number crunching capability of an 80486. The new radars being tested for NMD operate at much higher frequencies (allowing for higher resolution) and have much more powerful processors to allow for real-time discrimination. That info is transmitted to the interceptor as it goes in for the kill. I'm not positive, but I think the interceptor has some additional on-board capability to do discrimination as well.