On 8th June a magnitude 7.8 earthquake tore through the seabed off Sarangani, sending tsunami warnings across half the Pacific and collapsing buildings from General Santos to Davao Occidental [4, 8, 14, 21, 22, 24]. At least 41 are dead, over 20,000 displaced, and whole communities cut off by landslides [4, 5, 12]. The proximate cause is well understood: movement along the Cotabato Trench, the same subduction fault that produced the catastrophic 1970s Moro Gulf earthquake, which killed thousands [4, 11]. What remains stubbornly unclear is why, half a century later, the same geological threat continues to exact such a human toll.
The Cotabato Trench is not an emerging risk. It is a known, recurrent hazard. The Moro Gulf event—magnitude 8.0, striking in 1976—generated a tsunami that inundated coastal Mindanao and killed an estimated 5,000 to 8,000 people. Phivolcs has long identified the trench as a principal seismic zone. Yet multiple outlets report that this week's quake is being described as one of the most destructive to hit the Philippines in five decades [4, 11]—a framing that betrays how little has been internalised from the earlier disaster. Hospitals now operate outdoors because the buildings cannot be trusted [5]. Schools and critical infrastructure lie damaged [1, 5]. The power grid is down across swathes of the island, with the Department of Energy scrambling to restore supply [1, 19]. These are not the hallmarks of preparedness.