In the three decades since the end of the cold war, the leafy streets around Mimosa Plus Golf Course in Clark, an area about 92km north of the Philippines’ capital Manila, have been largely quiet, populated mainly by retirees.

But one day in April, about 100 US troops were sitting on a pavement and more spilling out of a hotel — a reminder of an era when Clark was the world’s biggest air base outside US territory.

“They’re back,” says onlooker Denmark Blances, a tourism student. “I’ve never seen so many US uniforms.” The troops were participating in Balikatan, or “shoulder to shoulder”, a large military exercise the US conducts annually with its oldest ally in Asia. This year it involved more than 17,600 members of the forces, the most since the US lost permanent access to Clark in 1991.