Does North Korea Really Have a Nuclear Bomb?
When India staged its first nuclear test in 1974, there were no doubts. It was a massive explosion estimated at eight kilotons (kt.) equivalent of TNT. Though it was conducted underground, it left a large crater on the surface. The test was celebrated in India, condemned in Pakistan and observed with caution in the rest of the world. After India's second series of tests in 1998, Pakistan responded with a five-device test set of its own two weeks later. Again, craters were made, congratulations offered, condemnations heard and medals given. India and Pakistan have been locked in a tense nuclear standoff ever since.
Russia, China, France, the United Kingdom, and of course the United States also had unambiguously "successful" first nuclear tests—if success means blowing up a big chunk of desert while poisoning the atmosphere with tons of radioactive debris. Of course, all five countries had massive science-industrial complexes to support their research, as did India. Pakistan did not, but China is widely suspected of having provided both the technology and the materials for Pakistan's first nuclear devices.
North Korea's nuclear tests, as so much else about the country, have taken a road less traveled. Its first test in 2006 was either a masterpiece of minimization, or a total fizzle at less than one kt. The second test in 2009 was a more nuclear-like five kt., but apparently a masterpiece of environmental good practice: the Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO) estimated that the containment of radioactive exhaust gas from the explosion "was above 99.9 percent."
The CTBTO dismissed the possibility of a faked nuclear test under the theory "that such a massive logistical undertaking would have been virtually impossible under the prevailing circumstances and would not have escaped detection." The CTBTO scientists apparently had never seen The Great Escape. But North Korea's "Dear Leader" Kim Jong-il was a great film buff, and any country capable of building a clandestine nuclear weapons program would presumably also be capable of sneaking high explosives into a remote mountain fortress under cover of darkness.
Rocket Man Goes Nuclear
After 2009, North Korea's nuclear testing program went back to sleep until the Dear Leader's son, "Supreme Leader" Kim Jong-un, needed to prove himself with a test of his own. It came in February, 2013. This test was at least a nuclear-sized twelve kt., unlike the previous two, though once again North Korea claimed a great technological leap forward, claiming it had tested a miniaturized warhead suitable for missile deployment.
Building a nuclear device is hard enough. Building one that can be deployed on an intercontinental ballistic missile (ICBM), launched into space, delivered to its target and then detonated is something else entirely. That was Kim Jong-un's threat.
But was the 2009 explosion even nuclear? The United States has conducted conventional explosion tests of nearly four kt. using chemicals packed into an forty-four-foot radius fiberglass hemisphere. Do the math, and a ten kt. explosion could be engineered in an underground chamber of roughly ninety feet (twenty-seven meters) cubed. That's not a lot of rock to be shifted to make room for a fake nuclear test.
The United States and Japan scrambled spy planes to sniff out the tell-tale radioactive xenon from North Korea's 2013 test, to no avail. But then, two months later, ground-based stations in Japan mysteriously detected the suspect chemical trail. It is possible that it took sixty days for the gases to waft the 600 miles from the test site. It seems just as likely that the Kim regime, coming to understand that the failure of international observers to detect radioactive gases cast doubt on its nuclear credentials, belatedly released gases to prove its test had been real.