Japanese soldiers 1939; Wikimedia Commons
Throughout the late 1930s, Japan and the USSR clashed repeatedly. In 1939, along the Mongolian border at Khalkin Gol – Nomonhan, the Soviet Army under General Georgy Zhukov defeated a large Japanese force. Japan subsequently abandoned plans to invade Siberia and in 1941 concluded a neutrality treaty with the USSR.
A friend sent me this interesting analysis from japan times that concludes:
“The main problem was Japan’s reliance on the spiritual superiority of its troops because it lacked the material wherewithal to match its opponents’ military machines. This vulnerability, compounded by poor intelligence gathering and careless overconfidence, translated into horrific casualties while also exposing weaknesses in Japan’s war planning and inadequate logistics. “