China’s lone aircraft carrier is prowling the Pacific as the country seeks to assert its military might and build up its naval warfare capabilities. The Liaoning carrier’s J-15 fighter jets practiced air confrontations and air refueling in the Yellow Sea late last week before the ship and its flotilla of escorting frigates and destroyers headed into the open Pacific beyond Taiwan and Okinawa. On Monday it headed to the South China Sea – the site of regional tensions caused by China building fortifications on disputed islands. It’s a move that hasn’t gone unnoticed by China’s Asian neighbors. Taiwan sounded a note of alarm, with its defense minister emphasizing the need for vigilance. “The threat of our enemy is growing day by day. We should always be maintaining our combat alertness,” said Taiwan Defense Minister Feng Shih-Kuan. Japan’s Defense Ministry, meanwhile, said it’s the first time it could confirm the Liaoning, which China bought from Ukraine in 1998, then rebuilt and commissioned in 2012 as a training vessel, had gone into the open Pacific. “We are taking notice of this event, which indicates China is expanding its ability to engage in maritime warfare,” Japanese Chief Cabinet Secretary Yoshihide Suga said. And it looks like that’s exactly the point China’s trying to make clear. A warning for Eastern Pacific China’s state-run Global Times media agency published an editorial on Christmas Day, timed to coincide with the aircraft carrier Liaoning’s maneuvers. The piece called on China to build up its fleet of aircraft carriers, make them combat ready, sail them to Eastern Pacific and look to set up naval supply bases in South America. The Global Times also said the drill is a sign the Liaoning’s combat capability has been enhanced and its areas of operation expanded, and could soon include the Eastern Pacific, including off the US West Coast. “When China’s aircraft carrier fleet appears in offshore areas of the US one day, it will trigger intense thinking about maritime rules. “If the fleet is able to enter areas where the US has core interests, the situation when the US unilaterally imposes pressure on China will change,” the Global Times said. The editorial called on China to speed up construction of homemade aircraft carriers “so as to activate their combat.” China is believed to have one new carrier near completion and another about to start construction, said Carl Schuster, a professor at Hawaii Pacific University and former director of operations at the US Pacific Command’s Joint Intelligence Center. But China’s ability to pose a long-range threat with aircraft carriers is a long way off, he said. A difficult buildup for China “China has no corps of experienced naval aviators and aircraft carrier crewmen on which to build their carrier force,” Schuster said in an email to CNN. “They are having to build it from scratch … a difficult challenge for a force reliant on 2-year conscripts for most of its personnel.” Schuster said China is planning for a fleet of four carriers by 2027-2029. Even with the additional carriers, its carrier fleet will only be less than half the size of that of the US Navy, which boasts 10 carriers in service, another near commissioning and another under construction. For now, though, the Global Times is pushing China to project power beyond the “first string” of islands around the country; an arc stretching from north of the Paracel Islands group in the South China Sea, northeastward to encompass Taiwan, west of Okinawa and north into the East China Sea between the Koreas and China. “As China’s only aircraft carrier fleet now, it should have the ability and courage to sail farther,” it said, “…to the waters where Chinese … fleets have never been.” And that would encompass waters of the Eastern Pacific.