Kerr and his family returned often to Beirut, during vacations and breaks from UCLA.[citation needed] In 1964–1965, an academic grant sent him to Cairo, where he worked on his most well-known book, The Arab Cold War, published in 1965. The next year he published Islamic Reform, a reworking of his doctorate dissertation. Following the 1967 Arab-Israeli War, Kerr sensed a drastic change for the worse in the tone of Arab politics, which became harsh and bitter.