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What doomed the Titanic is well known, at least in outline. On a moonless night in the North Atlantic, the liner hit an iceberg and disaster ensued, with 1,500 lives lost.

Hundreds of books, studies and official inquiries have addressed the deeper question of how a ship that was so costly and so well built — a ship declared to be unsinkable — could have ended so terribly. The theories vary widely, placing the blame on everything from inept sailors to flawed rivets.