The United States on Friday warned North Korea against testing such a missile, saying it would be a "provocative act."
There is no law against the test, so the United States cannot do much to stop it. The North Koreans have undoubtedly thought through the consequences and, as one expert said, they must have decided relations with the United States cannot get any worse, CBS News correspondent David Martin reports.
While the Bush administration has focused most of its recent attention on Iran's nuclear programs, many arms professionals insist the North Koreans pose a more immediate challenge.
"There is nothing more lethal than a country like North Korea having a long-range intercontinental ballistic missile with a nuclear warhead on it," Wendy Sherman, former adviser to President Clinton on North Korea, told Martin.
Sherman thinks North Korea's actions are an attempt to grab attention, saying they want "to make people to understand that they not only have this technology but they've shared this technology with many countries around the world, including Iran."
Officials in Japan and the United States have said that the North Korean government appears to be stepping up preparations to test a long-range Taepondong-2 missile and that a test may be imminent. Such a missile could potentially reach parts of the United States.
"They probably increased their nuclear arsenal by six to eight weapons while President Bush has been in office," said Michael O'Hanlon, a national security analyst at the Brookings Institution. "And, meanwhile, Iraq and Iran have made a grand total of zero weapons."
North Korea tested an earlier version in 1998 and it caused a worldwide uproar.
That missile flew over Japan, but its third stage failed to ignite and pieces plunged into the northwestern Pacific Ocean. Now, Western experts fear North Korean engineers have improved the technology.
Mr. Bush famously linked North Korea, Iran and prewar Iraq as an "axis of evil" in his January 2002 State of the Union speech. But the weapons of mass destruction Mr. Bush claimed Saddam Hussein possessed were never found. And Iran is not believed to have any nuclear weapons, although its uranium enrichment program is the center of intense attention.