Ask Americans what Greece has contributed to civilization, and the answers come readily: democracy, philosophy, theater, the Olympic Games. Homer. Socrates. Plato. Aristotle.Even our runners carry a Greek battlefield’s name across finish lines. But how many pause to consider Marathon — or ask what the Greeks have done since antiquity? Wednesday, Oct. 28, was the 86th anniversary of Oxi Day; Americans ought to look beyond ancient Greece. Modern Greeks have repeatedly stood beside us, sometimes at extraordinary cost. In 1805, at Derna, in present-day Libya, 38 Greek mercenaries joined eight U.S. Marines and other members of William Eaton’s expedition during...