Its military satellites crisscross the continent, keeping a watchful eye on army exercises with our allies. Its weapons are dispatched to all corners of the globe, from the Republic of Congo in Africa, to Venezuela in Latin America, and across Asia from Myanmar to Indonesia. But for much of the past 15 years, China has been developing a different kind of bomb, one that now has become increasingly unstable and that threatens to detonate from within. Until recently, the Middle Kingdom was considered an economic miracle with its transformation from dirt poor subsistence economy to a sophisticated global power the...