North Korea has long used illegal enterprises (drugs, counterfeiting, smuggling, espionage), run out of their embassies as a way to earn more foreign currency. This caused a growing number of countries to threaten a shutdown of the North Korean embassy they hosted and after the 1990s (a particularly desperate time for North Korea) a lot of the illegal activities were either shut down (like drug smuggling) or done a lot more discreetly (smuggling of non-drug items and distributing counterfeit American hundred dollar bills) to avoid losing these foreign embassies.
Despite that since 2000 illegal drugs have still been coming out of North Korea. The difference now is the government is not producing the drugs. While technically illegal the North Korean government sort of tolerated non-government manufacturing of methamphetamine, if only because the drug was so popular among so many North Koreans who had money. But that tolerance has turned into a problem with a growing number of methamphetamine producers exporting their product. Like the government, all North Koreans want more foreign currency. Most of these smugglers are being caught in China, where methamphetamine addiction has become a major problem. But it goes farther than that. In late 2013 five men were arrested in as they prepared to smuggle 100 kg (220 pounds) of 99 percent pure North Korean methamphetamine to the United States via Thailand. North Korea has long been a major supplier of methamphetamine in the region, but using Thailand as a jumping off point for methamphetamine smuggling into North America was new. Because of the U.S. connection Thailand extradited the five (who are British, Filipino, Taiwanese and Slovakian) to the United States for prosecution and, one presumes, intense interrogation.
Meanwhile there is a growing problem with North Koreans obtaining meth and becoming addicted. This is a serious problem because most of the people with enough money to support a drug habit are from the small ruling class and the growing number of market entrepreneurs. In the last few years the government has ordered the security forces to crack down on drug dealers. Peddling this stuff is very lucrative, as a gram of meth goes for over $250 on the street and it costs a lot less than that to get it from corrupt officials in the meth production operation. Addicts within the government are more prone to steal government assets, or even sell information to foreigners.
Tribal drug lords in northern Burma are the other big source of meth, which has become hugely popular in China and throughout East Asia. China wants to keep the Korean and Burmese meth out and is having more success on the heavily guarded North Korean border. This means non-government North Korean meth producers have to find another market and some have put more meth into circulation within North Korea. Thus the effort to establish an American connection.