Three fully militarised Beijing-backed bases in the South China Sea pose a threat to Australia’s vast northern region, according to Adm. John Aquilino, commander of the U.S. Indo-Pacific Command. The leader of the United States’ largest command—which includes 380,000 army, marine, air force, and navy personnel spread across 14 time zones—visited Darwin, Australia on March 23, after flying over the South China Sea. “They are full-fledged offensive bases,” he told reporters in comments obtained by AAP. “Runways, hangers, barracks, anti-aircraft missiles, anti-ship missiles, jamming capability, hangers for fighter aircraft, bomber aircraft … That is fact.” When questioned about the threat to Australia’s north, Aquilino said, “There is certainly a threat.” “Today in the Indo-Pacific, it hosts the most concerning security challenge that we have faced in a number of years,” he said. The admiral is in Australia to inspect the U.S. marine contingent in Darwin, and to work closely with …