Eleven days ago, a team of earthquake experts published a scientific paper precisely describing how the titanic tsunami-generating earthquake off Sumatra on Dec. 26 greatly raised risks of a fresh offshore earthquake. The earthquake they described was almost exactly like the one that struck yesterday. The paper's authors and other experts had calculated how the December shock increased stress on the adjacent section of the Sunda Trench, a seam in the earth's crust where one plate dives beneath another. The pressure greatly increased the chance that the seam would fail, they said. The new earthquake was generated when the plates...