From the Sunda Strait, where geology and human ambition have long negotiated an uneasy coexistence, Mount Anak Krakatau reasserted its primacy in the early hours of September 6, sending volcanic ash drifting across Jakarta and forcing Soekarno-Hatta International Airport to suspend operations until 9:30 in the morning. Thirty-three flights — among them international services threading the region together — were caught in the pause, a reminder that the archipelago's skies are never entirely free from the forces that shaped it. Officials moved swiftly to rule out tsunami risk, but the ash contin