North Korea announced it detonated a nuclear weapon, drawing strong protest from the United States, with President Bush vowing “an immediate response by the United Nations Security Council.”

But he didn’t specifically mention any possible U.S. military response

If North Korea takes the further step of transferring nuclear weapons to rogue states or “non-state” terrorist groups, that “would be a grave threat to the United States,” Bush said.

He added that the United States “would hold North Korea fully accountable for the consequences of such action.”

But how the United States would know if North Korea sold an atomic bomb to, say, Iran or al Qaeda is unclear.

Military analysts have said if a nuclear device were smuggled into the United States in any of millions of cargo containers entering U.S. ports, there would be no “fingerprints” – no way of identifying who smuggled the weapon and who detonated it in a U.S. city.

Bush didn’t say just what the United States will do in the face of North Korea violating non-proliferation rules and detonating the bomb underground despite being warned not to by the West.

The president did, however, issue a non-specific call “to achieve the de-nuclearization of the Korean Peninsula.”

North Korea also is developing long-range Taepo Dong-2 missiles capable of reaching North America, but one of these missiles failed shortly after launch as Americans celebrated on the July 4 holiday.

Earlier, in 1999, North Korea launched a mid-range Taepo Dong-1 missile that arced over Japan and plunged into the Pacific Ocean.

“I reaffirmed to our allies in the region, including South Korea and Japan, that the United States will meet the full range of our deterrent and security commitments,” Bush said. He also conferred with leaders of China and Russia.

“Once again, North Korea has defied the will of the international community, and the international community will respond,” Bush said. That might involve the U.N. Security Council imposing even more economic sanctions on the isolated rogue regime.

“We reaffirmed our commitment to a nuclear-free Korean Peninsula, and all of us agreed that the proclaimed actions [underground nuclear blast] by North Korea are unacceptable, and deserve an immediate response by the United Nations Security Council,” Bush said.

“I reaffirmed to our allies in the region, including South Korea and Japan, that the United States will meet the full range of our deterrent and security commitments.”

The North Korean moves over several years to develop both nuclear weapons and long-range ballistic missiles are a major reason the United States is working rapidly to erect a multi-layered ballistic missile defense shield.

North Korea is estimated to have an arsenal of perhaps 10 or so nuclear weapons in violation of nonproliferation agreements.

This demonstrates the critical need for the United States to create a multi-layered missile shield now in development, according to a Washington group, the Missile Defense Advocacy Alliance (MDAA).

If North Korea can test a nuclear weapon successfully, then such a device might be mounted as a warhead on a missile, some military analysts have cautioned.

However, Michael O’Hanlon, senior fellow with the Brookings Institution think tank in Washington, said on WTOP it is unclear whether the North Korean bomb design is sufficiently small to fit atop a long-range missile.

As well, perhaps the international community can prevent the situation from becoming even worse, he said in a Brookings statement. “Even though it is too late to prevent North Korea from having the plutonium for perhaps ten bombs, it is not too late to prevent North Korea from becoming an industrial-scale producer of weapons,” he explained.

“We as a nation must have a deployed [missile defense] capability 24/7 composed of operational integrated missile defenses, on both sea and land, in and around the Korean Peninsula including Japan,” MDAA asserted.

MDAA added that “Russia, China, Japan and South Korea” must come together with the United States “to stabilize this situation and most importantly defend and deter against short, medium and long-range missiles from North Korea.”