The selected Hata for a part of what historian James William Morley described as a team of "young, objective diplomatic and military historians" to be given unprecedented access to primary source records to write the history of the origins of World War II in Asia. The result was "Taiheiyō sensō e no michi" ("The Road to the Pacific War"), published between 1962 and 1963 and then translated into English in the 1970s and 1980s. Hata contributed three essays to the series. Roger Dingman described the first, "The Japanese-Soviet Confrontation, 1935–1939", as "a wealth of new data", and praised the second, "The Army's Move into Northern Indochina", for demonstrating "brilliantly how peaceful passage through northern Indochina became forceful occupation". Mark Peattie wrote that Hata's third essay, "The Marco Polo Bridge Incident 1937", was "the best overview we now have in English" of the event, and Hata would later expand it into a full-length book which Edward Drea and Tobe Ryoichi called "the single best source on the incident".