While the world focuses on the dangers posed by North Korea's nuclear weapons program, a separate danger - the communist state's ballistic missile development program - lurks in the background. That danger was highlighted again recently by Pyongyang's offer to cooperate on missile technology with Nigeria.
A high-ranking North Korean official visited Abuja, Nigeria, in late January, where he came close to signing a missile deal with the government. A Nigerian statement said the two nations were planning to sign a memorandum of understanding to forge "a program of cooperation that included missile technology."
Nigeria says it wanted to buy a North Korean missile system for peacekeeping and security purposes. It defended its right as a sovereign nation to make such a deal, and denied that it had any desire to possess weapons of mass destruction. But after the United States hinted at sanctions, Nigeria walked away from the planned partnership.
Woo Seong-ji, a professor at the Institute of Foreign Affairs and National Security in Seoul, says missile technology agreements between North Korea and other nations are an ongoing concern of the United States and its Asian allies.
"I think North Korea has been engaging in this kind of activity for a long time, so its missile technology is pretty advanced," he said. "It has already sold this technology to a number of countries to earn cash."
The U.S. government believes, in fact, that North Korea is the world's leading missile exporter, and says Pyongyang has earned more than $1 billion from such sales over the last 11 years.
It is believed to have cooperated on missile technology with Libya, Iran, Syria, Egypt, Yemen and Pakistan. In the 1970s it traded missile technology with China and the Soviet Union, but those partnerships dissolved as the Soviet Union collapsed and China began integrating itself more broadly with the non-communist world.
Mr. Woo says North Korea, whose economy is close to collapse, depends on sales of missile technology to earn hard currency, since most of the goods it produces are not attractive to international markets.
But he also believes that even an attempted sale, like Pyongyang's approach to Nigeria, packs a potent political message for the rest of the world, especially ahead of the multi-party talks on Pyongyang's nuclear program due to begin in Beijing on February 25.
"North Korea might be trying to get upper hand by revealing this news to the concerned parties of the six-party talks, that it is always ready to sell its missile technology if the United States and other countries do not come to the negotiating table," said Woo Seong-ji.
While much about the country's missile program remains a secret, it is known that Pyongyang has made missile development a top national priority for more than 30 years. The country's late founder, Kim Il Sung, established a military academy in the 1970s with the express purpose of training scientists and other experts to develop missiles.
Despite North Korea's extreme poverty, the Bush Administration believes the government still commits extensive resources to this area.
The North Korea's missile capabilities became a startling reality to the rest of the world in 1998, when Pyongyang launched a three-stage ballistic missile that flew over Japan. The launch was only a test and the missile landed harmlessly in the ocean. But the message was clear: within minutes of being fired, North Korean missiles could hit Japanese territory.
That frightening display has become a major security concern for Tokyo. After years of debate, Japan will soon purchase a multi-billion-dollar, U.S.-designed missile defense system, primarily to protect itself against a potential North Korean attack.
Daniel Pinkston of the Center for Nonproliferation Studies in Monterey, California, is an expert on North Korea's missile program. He says Kim Jong Il, the North Korean leader, is not likely to eliminate the program in the short term, because it could cause instability and economic problems for Mr. Kim's rule.
"They have a lot of engineers and scientists and military people who are involved in the production of ballistic missiles," he said. "It is very difficult for them to shut down the program without offering some alternative employment for those people."
But Mr. Pinkston also says an abrupt end to the missile program could create a situation that even the United States might not like to see.
"A second issue is that it is in the interest of the United States that these people have jobs, so that they do not go overseas or to other countries and sell their expertise and the missile technology," said Mr. Pinkston.
Previous U.S. administrations have attempted to deal with this issue. The Clinton Administration, for example, had discussions with Pyongyang on how the factories producing missiles and missile parts could turn to the production of different items, such as satellites, that could be exported to the United States.
Officials in the Bush Administration are now looking at various scenarios for helping North Korea move out of the missile business and enter other industries on a competitive footing, but a specific plan has yet to be worked out.