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Yemen was Egypt's Vietnam
Washington Post
https://www.washingtonpost.com/news/worldviews/wp/2015/03/28/how-yemen-was-once-egypts-vietnam/
"In this terrain," the New Republic explained with Orientalist relish in 1963, "the slow-moving Nile Valley peasant has proved a poor match for the barefoot, elusive tribesmen armed only with rifle and jambiya -- the vast, curved, razor-sharp dagger which every male Yemeni wears in his belt."
At the peak of deployments, Nasser committed as many as 70,000 Egyptian soldiers to Yemen. After the war's end in 1970, Yemen remained a republic, but Egypt had paid a terrible price: More than 10,000 Egyptian soldiers died and the country ran up massive war debts. The conflict has been dubbed "Egypt's Vietnam," and is cited as one of the reasons why the Egyptian military suffered such a withering defeat in the Six-Day War with Israel in 1967.