Hui Zhang

Articles by Hui Zhang

16 January 2012

The defensive nature of China's "underground great wall"

Hui Zhang

There has been a lot of prominent discussion lately (in the Washington Post and Wall Street Journal, among other places) about the size of China's nuclear arsenal, based on a study by Georgetown University professor Phillip Karber, "Strategic Implications of China's Underground

23 July 2009

Is North Korea's reprocessing facility operating?

Hui Zhang

In response to a U.N. resolution punishing its nuclear test on May 25, North Korea defiantly threatened on June 13 to weaponize all of its newly separated plutonium. Pyongyang also declared, "More than one-third of the spent fuel rods has been reprocessed to date." However, recent off-site air samples and satellite imagery suggest that North Korea's reprocessing facility isn't operating, casting doubt on Pyongyang's statements. But is it possible that North Korea's reprocessing facility could be in use without detection?

18 June 2009

Assessing North Korea's uranium enrichment capabilities

Hui Zhang

As retaliation against tighter U.N. sanctions, on Saturday North Korea defiantly threatened to expand its nuclear arsenal and begin a program of uranium enrichment--a threat it first made in response to U.N. condemnation of its early April rocket launch. Compared to North Korea's well-known plutonium production program, the nature of Pyongyang's highly enriched uranium (HEU) program is less clear.

2 June 2009

The North Korean nuclear test: The Chinese reaction

Hui Zhang

On the morning of May 25, many schools in northeast China were evacuated because of the earthquake caused by the North Korea nuclear test. The epicenter of the earthquake, registering 4.5 on the Richter scale, was just 180 kilometers away from those schools.

1 September 2005
In its own way, China is actually trying to influence North Korea.
1 July 2001
Commercial satellites can be used to pick up many of the telltale signs of fissile material production.