Why did Japan attack the US? There are a number of reasons such as the Washington Naval Treaty as well as the oil embargo and other restrictions imposed on July 26th, 1941. Here is one from a new book, Japan 1941: Countdown to Infamy by Eri Hotta. Check your public library. from Japan 1941 by Eri Hotta. In 1941 -- before the attack on Pearl Harbor -- the United States imposed sanctions on Japan as a response to the Japanese invasion of China, aggression in French Indochina, and its alliance with Germany and Italy. Japan was crippled by these sanctions. First, luxury goods disappeared. Then, the more fashionable adopted plain and simple dress. Next, Japanese rice -- a revered cornerstone of Japanese society -- was rationed until it practically disappeared, replaced by imported rice. Finally, rations were reduced to fourteen hundred calories a day and the population was advised to be creative with supplementing their diet. "In everyday life, luxury goods had quickly disappeared, and there was a shortage of food, most noticeably the main staple, rice. As the conflict in China went on and on, those remaining in the countryside -- the best men had gone to the military and war-related industries -- faced increased pressure to produce more food for the troops. Starting in the summer of 1940, even the fanciest restaurants in Tokyo resorted to serving cheaper imported rice -- the drier kind some scornfully called 'mouse poops' -mixed with potatoes. After April 1941, in six major metropolitan cities once replete with all the conveniences of modem life, people could obtain rice only with ration coupons. By December 1941, this system applied to 99 percent of Japan. In a country where domestically grown rice occupied an exalted, almost sacred place in the national diet, this was seen as a scandalous hardship.