ZHUHAI, China - Chinese President Xi Jinping has elevated his country's missile forces to a level where they pose an unprecedented challenge to the aircraft carriers and bases that form the backbone of American military primacy in Asia, a Reuters special report reveals today.Many of the missiles in Beijing's arsenal now rival or outperform those of the United States, puncturing the protective umbrella that for decades America has afforded its regional allies South Korea, Japan and Taiwan.Captain James Fanell, a former U.S. Navy intelligence chief, told Reuters that China now has "the most advanced ballistic missile force in the world" and has "the capacity to overwhelm the defensive systems we are pursuing."Critically, China has forged a monopoly in one class of conventional missiles that enable it to strike at U.S. aircraft carriers off its coast and at bases in Japan or even Guam in the Pacific Ocean. Under a Cold War-era treaty between the U.S. and Russia, neither country has been allowed to develop these weapons – land-based, intermediate-range ballistic and cruise missiles with a range between 500 and 5,500 kilometers (3,418 miles). But China, which isn't a signatory to the treaty, has been deploying these rockets in massive numbers.Today's special report is part of "The China Challenge," a Reuters series on how Xi Jinping is reshaping and rejuvenating China's military, the People's Liberation Army (PLA), by filling its top ranks with loyal allies and enhancing its missile, naval and nuclear capabilities.Previously in "The China Challenge" - Inside Xi's remaking of the world's largest fighting force: https://reut.rs/2Uzr9z4In the event of a confrontation in the seas off its coast, Chinese military brass say they now have the means with which to keep American carriers at bay. "We cannot defeat the United States at sea," a retired PLA colonel told Reuters. "But we have missiles that specifically target aircraft carriers to stop them from approaching our territorial waters if there were conflict."That is a potentially dramatic development, signaling that China is able to deter U.S. intervention as it expands its control in the South China Sea, steps up naval and air sorties around Taiwan, and extends its operations into areas it disputes with Japan.With the United States suddenly finding itself on the wrong side of the missile gap, American military planners face a new and daunting scenario. Because some of China's anti-ship missiles now outrange the fighter jets aboard U.S. carriers, they could neutralize American flattops in a conflict. If these carriers are forced to operate outside the range of their aircraft, they would be far less potent.The United States, which has long been preoccupied with wars in the Middle East and Afghanistan, is now rushing to claw back the advantage. President Trump announced on Feb. 1 that Washington would withdraw from its missile treaty with Russia in six months, clearing the way for the U.S. to begin building the ground-launched missiles banned for more than three decades.China's Ministry of National Defense, the U.S. Indo-Pacific Command and the Pentagon did not respond to questions from Reuters.