China’s “Underground Steel Great Wall” could “guarantee the security of the country’s strategic arsenal” against potential attacks including those from future hypersonic weapons, Qian Qihu, recipient of the country’s highest science and technology award, told the Global Times… The “Underground Steel Great Wall” is a series of defense facilities located deep under mountains. While the mountain rocks are thick enough to resist enemy attacks, entrances and exits of these facilities are often vulnerable, and Qian’s work was to provide extra protection to these parts.- Global Times Photo courtesy: Deng Xiaoci/GT