 Ramba uchiverenga ndima ino - Pashure pechiitiko cheJapan chebhendi yenhema Mukden muna 1931, kupfura kweJapan kwechikepe cheAmerica cheUSS Panay muna 1937, uye kuurayiwa kwevanhu muNanjing muna 1937-38, hukama hweJapan neAmerica hwakakanganisika. Muna 1939, United States yakazivisa Japan kuti yaisazowedzera chibvumirano chayo chekutengeserana uye maonero evanhu vekuAmerica vaipikisa kuwedzera kweJapan kwakatungamira kune akateedzana ezvirango zvehupfumi, iyo Export Control Acts, iyo yakarambidza kutengeswa kweUS kwemakemikari, zvicherwa uye zvikamu zvemauto kuJapan uye yakawedzera kumanikidza kwehupfumi kuhurumende yeJapan. Mukati ma1939 Japan yakatanga kurwisa kwayo kwokutanga paChangsha, guta reChinese rinokosha zvikuru, asi rakadzoswa mukupera kwaSeptember. Pasinei zvapo nokudenha kunoverengeka kunobva kumativi ose ari maviri, hondo pakati peChina neJapan yakanga yakamira muna 1940. Kuti awedzere dzvinyiriro paChina kupfurikidza nokuvhara nzira dzokugovera nadzo, uye kuti agadzire zviri nani mauto eJapane muchiitiko chehondo nemasimba okuMadokero, Japan yakapinda ndokubata Indochina yokuchamhembemuna September 1940. 