Robert Egan has a pretty good feel for how desperate the CIA is for scraps of information about North Korea.
Egan has served barbecue to North Korean diplomats at his restaurant in Hackensack, N.J., for 15 years, and he has visited Pyongyang, the North Korean capital, several times. He also has fed details about his customers to U.S. authorities, even plucking stray hairs off their suits so American officials could trace the DNA. Not surprising, he has found FBI surveillance equipment hidden in his office.
U.S. intelligence is "using a guy who flips burgers for a living" to understand North Korea, said Egan, a 53-year-old high school dropout whose odd role as a citizen ambassador has been optioned as an HBO movie.
U.S. officials downplay their interest in Egan, but they don't deny that they are hungry for insight on a nuclear armed nation that is possibly the world's toughest to spy on, a virtual black hole for most intelligence agencies.
The latest evidence: U.S. officials apparently were unaware for 51 hours that longtime leader Kim Jong Il had died Dec. 17, hearing the news only when it was announced on North Korean TV. They now are scrambling for the skinny on his youngest son and appointed successor, Kim Jong Un, a chubby 27-year-old known to enjoy playing video games.
More important, despite the near-constant gaze of spy satellites, U.S. intelligence agencies were stunned to learn from Israeli officials in 2007 that North Korean scientists had helped Syria build a secret nuclear reactor in the desert. Israeli warplanes bombed the site when President George W. Bush declined to do so.
Similarly, U.S. intelligence was caught off guard in November 2010 when North Korean officials took a visiting American scientist on a tour of a newly constructed uranium enrichment facility that is making low-level reactor fuel but could be converted to produce highly enriched uranium for nuclear weapons.
The site "is a good demonstration of just how limited overhead imagery is, and how small the footprint of a centrifuge enrichment facility is," the scientist, Siegfried Hecker, a former director of the Los Alamos National Laboratory, wrote in an email.
"There is likely a facility somewhere else that may be making … bomb fuel," said Hecker, who now teaches at Stanford University.
U.S. officials cite the limits of espionage in a Stalinist state where modern communications barely exist, few citizens are allowed to travel abroad and foreigners are not welcome.
"The society as a whole is not well connected," said Rep. Mike Rogers (R-Mich.), chairman of the House Intelligence Committee. "The government is not well connected. They don't communicate well amongst themselves. Everything tends to be compartmentalized."
Bruce Klingner, the CIA's top analyst on North Korea from 1996 to 2001, said understanding North Korea is like discerning the picture on "a jigsaw puzzle when you have a mere handful of pieces and your opponent is purposely throwing pieces from other puzzles into the box."
But Klingner disputes the notion that North Korea is so poor or backward that it is not a formidable adversary. It not only has built and tested crude nuclear weapons and ballistic missiles, but it also is adept at counterintelligence and cyber warfare.
"We have this image of North Korea being this technically bereft country, but they put their emphasis on certain areas," Klingner said. "South Korea sees North Korea's cyber attack capabilities as equal to the CIA's."
In April, 30 million customers of South Korea's Nonghyup bank were unable to use ATMs or access online accounts for several days after a suspected North Korean cyber attack on the bank, analysts said.
The challenge for Western spy services is immense. Unlike Iran, where resistance groups have funneled valuable nuclear intelligence to the West, North Korea is a totalitarian state that allows no political opposition or even mild dissent.
"Three generations of family members have been sent to the gulags" after one person criticized Kim Jong Il, said Klingner, now a fellow at the Heritage Foundation in Washington.
Washington has no embassy in Pyongyang to provide cover for CIA or other intelligence officers. The few Western diplomats or aid workers who live there are closely monitored by state security.
North Korean diplomats who are posted abroad, whom Western spy services normally would seek to recruit, reportedly are forced to leave a close relative at home as leverage to ensure that they don't betray the regime.
U.S. eavesdropping systems are of limited use. Few North Koreans use cellphones, access to the Internet is barred, and the regime has developed its telecommunications on a system of buried fiber optic cables that are difficult to tap. Mountainous terrain complicates satellite reconnaissance, and the military hides facilities in a vast network of tunnels.
China, Pyongyang's closest ally, appears the best informed on events in North Korea. Joong Ang Ilbo, a leading South Korean newspaper, reported that China's ambassador to North Korea told his government of Kim's death hours after it happened.
U.S. interests in North Korea are chiefly focused on its nuclear and missile programs, exports of illicit weapons technology and military movements that might endanger South Korea, where 30,000 U.S. troops are stationed.
In May, in a victory for Western intelligence, a U.S. Navy destroyer shadowed a freighter in the South China Sea that U.S. officials believed was carrying North Korean missile parts to Myanmar. Both Asian countries are under strict United Nations trade and weapons sanctions, and the freighter's captain ultimately turned back. A similar episode occurred in 2009.
But the obstacles to reliable intelligence leave U.S. officials with little confidence that they can predict how the new leaders in Pyongyang will behave.
"Of course there's always a need for more information on a place like North Korea, and folks are working toward this goal every day," said a U.S. official with access to current intelligence.
Mark Lowenthal, a former top CIA analyst, offered a more candid assessment.
"We're not omniscient," he said. "We have no idea what's going to happen, and then again, neither do the Koreans."