MELBOURNE, Australia — A paper published by the Chicago, Illinois-based Bulletin of the Atomic Scientists has estimated that China has 350 nuclear warheads, significantly more than that estimated by the U.S. Defense Department.The report, written by Hans Kristensen, the director at the Nuclear Information Project at the Federation of American Scientists, and Matt Korda, a research associate at FAS, arrived at the number by counting both operational warheads and newer weapons “still in development.”These weapons include hypersonic missiles, silo-based and road-mobile intercontinental ballistic missiles, and their submarine-launched equivalents, bringing the total number of nuclear warheads to more that the “low...