In Emperor Hirohito's announcement of the end of World War II, there was a section that's been translated into English as "not necessarily to Japan’s advantage".
But now the war has lasted for nearly four years. Despite the best that has been done by everyone – the gallant fighting of the military and naval forces, the diligence and assiduity of Our servants of the State, and the devoted service of Our one hundred million people – the war situation has developed not necessarily to Japan's advantage, while the general trends of the world have all turned against her interest.
The phrase has sometimes been interpreted as an understatement, for example this blog post interpreted it that way.
I came across a blog post saying that maybe the statement was difficult to translate accurately, but I don't know how expert the person being quoted by the blog post is.
I'm aware that the Japanese used in the speech is very different from everyday Japanese. I'm not interested in learning how to understand the Japanese used in that speech, but knowing whether understatement is used in Japanese.
Was "not necessarily to Japan’s advantage" meant to be an understatement?