Indonesia's New Mourning

For the past month the citizens of Yogyakarta have warily watched Mount Merapi, an active volcano 25 km from the ancient Indonesian city. Scientists warned that Merapi was ready to erupt, and thousands of villagers living on its slopes were evacuated as a precaution. So far Merapi hasn't blown. Instead, Yogyakartans discovered on Saturday that the real danger was the ground beneath their feet.

At 5:54 a.m. the city of 3.2 million was rocked by a 6.2-magnitude earthquake that struck offshore, just 24 km to the southwest. Feeling the tremor, thousands of families fled into the streets and...