Deep in the outback, a flurry of construction by Australia and the United States is transforming this once quiet military installation into a potential launchpad in case of conflict with China.

Runways are being expanded and strengthened to accommodate the allies’ biggest airplanes, including American B-52 bombers. A pair of massive fuel depots is rising side by side to supply U.S. and Australian fighter jets. And two earth-covered bunkers have been built for U.S. munitions.

But the activity at RAAF Tindal, less than 2,000 miles from the emerging flash points of the South China Sea, isn’t unique. Across Australia, decades-old facilities — many built by the United States during World War II — are now being dusted off or upgraded amid growing fears of another global conflict.

Marles declined to comment on the increasing rotations ... but said the trajectory is “an increasing American force posture in Australia.”