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Historian Andrew Roberts' latest book, Masters and Commanders, was published in the UK in September. His previous books include Napoleon and Wellington, Hitler and Churchill, and A History of the English-Speaking Peoples Since 1900. Roberts is a fellow of the Royal Society of Literature.

If Egypt’s revolution is successful, the U.S. will lose an influential ally, says Andrew Roberts—and if history is any guide Obama may wish Mubarak had remained in power. Plus, full coverage of the Egypt protests.