An incredible story from World War I : the great port city of Halifax, Canada, is practicaly dmeolished by the most powerful explosion ever visited on a human population (until Hiroshima and Nagasaki). It was a terrible maritime accident of ships bearing munitions for the Allid troops in Europe, that caused 11,000 casualties on Dec. 6, 1917. Even mor eincredible was how cities acorss New England, especially Boston, responded to help.