Sri Lanka, Dec. 1 -- Cyclone Ditwah has left behind an immense trail of death and destruction across Sri Lanka - deadly landslides, entire families buried under collapsing earth, hundreds dead and hundreds more still missing, roads washed away, homes inundated, and communities stranded for days without food, clean water, or medical assistance. Even as rains subside and floodwaters gradually recede, new dangers continue to emerge. Water levels in the Kelani River remain critically high, posing a severe and immediate threat to the Colombo District, where overflowing banks could unleash yet another wave of displacement and destruction in the country's most densely populated region.

This is not an isolated regional disaster. From the Central...