Kim Jong Il, center, at an undisclosed location in North Korea in 2009. (KCNA via Reuters)

Now this important cash crop has nearly evaporated, and North Korea bears much of the blame. According to a new analysis, North Korea did so well at marketing its missiles that it eventually put itself out of business.

In recent years, customers like Iran and Pakistan have increasingly transformed themselves from missile importers to missile manufacturers, building their own weapons in factories often designed and constructed with North Korean expertise, said the study by Josh Pollack, a consultant to the U.S. government on arms control. For those countries and others, building one’s own missiles was both cheaper and safer, limiting the risks of interference or pressure from the United States and other Western powers.

“North Korea’s customers no longer wanted to buy missiles,” Pollack said at a recent panel of the Center for Nonproliferation Studies in Washington. “They wanted to have their own missile factories, and the North Koreans were prepared to help.”

Pollack, a featured blogger at the Arms Control Wonk Web site, pulled together nonclassified figures on North Korea missile exports for the past three decades, relying in part on reports of intercepted North Korean shipments. He found that, in the 1980s, Pyongyang was by far the world’s biggest supplier of missiles, surpassing China and Russia. It sold about 420 missiles between 1987 and 1993.

By contrast, only 60 missiles are known to have been sold by North Korea to foreign partners in the past five years, Pollack said. With fewer missile customers, Pyongyang officials have had to supplement the country’s diminishing hard-currency requirements by selling missile components and conventional arms instead of whole missiles, he said.

Pollack credited the sales slump in part to a set of global nonproliferation programs — including the 2003 Proliferation Security Initiative — that has raised the costs for many countries doing business with the North Koreans. Countries such as Egypt have been pressured by the United States and European powers to halt weapons-related trade with the communist government, making the idea of missile self-sufficiency more attractive, he said.

“The overall pattern is like a narrowing funnel,” Pollack said, “with fewer relationships over time.”

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