Secretary of Defense Robert Gates refused a request from the U.S. Northern Command to use the high-powered SBX radar to track the illicit launch and flight of the North Korean long-range missile that arced over Japan April 5, The Washington Times reported.

That launch and ballistic flight occurred just a day before Gates unveiled a plan to slash spending on missile defense by about $1.4 billion in the next fiscal year, from a prior annual level of about $10 billion. (Please see Space & Missile Defense Report, Monday, April 6, 2009.)

The report quoted a spokesman for Gates saying that other radars could be and were used to track the missile, and quoted another source as saying that the SBX radar was undergoing maintenance at the time. Therefore, the request from Air Force Gen. Gene Renuart, commander of the Northern Command, to use the SBX radar was denied.

But using the SBX radar could have given U.S. missile defense forces the option of using the best radar data if they had opted to shoot down the North Korean weapon. A shoot- down would have shown, against a genuine rogue state missile, the value and reliability of U.S. multilayered missile defense systems.

Even without a take-down, the SBX still could have provided American analysts precisely detailed data on the North Korean missile, its flight and operation.

Retired Air Force Lt. Gen. Henry A. “Trey” Obering III, former director of the Missile Defense Agency (MDA), has said the SBX sea-going, mobile radar possess phenomenal powers, able to detect a baseball-sized object in the air from 3,000 miles away.

In any event, even absent any attempt to shoot down the North Korean missile, using the SBX radar to track it would have provided the most realistic test of the U.S. missile defense sensor system, against an actual North Korean launch.

Critics of missile defense in Congress and elsewhere frequently say that more realistic testing is required before full funding of the multi-layered defensive system is warranted.

As matters transpired, however, North Korea threatened dire action such as war if the United States or Japan used missile defense systems to shoot down the missile, and the United States and Japan didn’t attempt to shoot it down.

U.S. surface combatant ships equipped with the Aegis weapon control system and Standard Missile-3 interceptors stood by during the North Korean launch, and a similar Japanese Aegis system also was in position. U.S. officials said they could have shot down the missile if it had headed toward U.S. territory.

The missile, the Taepo Dong-2, is thought to have a 4,000-mile range, enough to strike Alaska or the West Coast of the United States. With upgraded fuel, its range could be longer, according to Obering.

In the test flight two weeks ago, the North Korean rocket functioned well in the first stage, and flew a substantial distance in the second stage. But the third stage apparently failed to separate and burn properly, so that the top of the missile — either a satellite as North Korea claimed or a dummy warhead — flew only about 1,240 miles before falling into Pacific waters.

Still, that would have provided not just a realistic, but an actual rogue state missile to test the capabilities of the U.S. missile defense system, if a shoot-down had been permitted as the missile blazed on a track toward Japan.

Gates last week defended his move to cut spending deeply for certain missile defense systems, saying the United States still has adequate programs. (Please see separate story in this issue.)