In early December, the People’s Liberation Army's (PLA) publication, China Defense Daily (Zhongguo Guofang Bao), published a report that provided a rare glimpse into an underground tunnel that is being built by the Second Artillery Corps (SAC)—the PLA's strategic missile forces—in the mountainous regions of Hebei Province in northern China. The network of tunnels reportedly stretches for more than 3,107 miles (Ta Kung Pao, December 11; Xinhua News Agency, December 14). The revelation of the semi-underground tunnel highlights the strides being made by China's nuclear modernization efforts, and underscores a changing deterrent relationship between the United States and China. China's...