This is a long-winded series of questions so sorry in advance - I’ve been reading about Japan in WW2, there are a few things I’m not totally clear on, and I thought it best to group them together. Feel free to answer any part - thanks for any and all responses
Why did the Allies allow Hirohito to remain as Emperor of Japan after the end of the war? Was there any backlash in the West against this?
What are attitudes in Japan like concerning the Nanking massacre? Is denialism confined only to extremist nationalists or is it more prominent?
According to Wikipedia, “The Taiwanese people reportedly never have the same empathy towards the mass killing event as their Chinese Mainlander counterparts do”. Why is this?
I can try to answer the first part. But I am not a professional historian.
There was a process against war criminals in japan, but it was never as big as the Nuremberg trial and the Imperial family was never put to trial. This was mainly MacArthur doing. MacArthur was the supreme commander of the allied forces in the pacific and later oversaw the allied occupation.
MacArthur knew of the importance of the imperial throne as a sign to the Japanese.
It was much easier to have a peaceful occupation of Japan and having Japan pursue a democratic path as long as the Emperor supports such a path.
The Throne had also very good connections to all the political elites, which was important since the Japanese government was not dismantled.
And the Throne cooperated fully, as they knew it would be easier to build Japan up to a powerhouse on the world sage when they cooperate. The Emperor was also never that much of a militarist as for example Prime minister Tojo. This is not to say, that he didn't support the war.
The Emperor agreed also to say, that he wasn't a god. Which the USA thought would be the position of the Emperor. And while as far as I understand Japanese Culture, the line of Emperor always claimed to be descendants gods. So for the Japanese this was not too big of a change, but the USA was happy about it.
MacArthur also seemed to respect the Emperor personally. Please keep in mind that as soon as it is about relationships between people it is difficult to make a reliable statement.
One rather important meeting was when Hirohito came early in the morning to the house of MacArthur. Not everything of the meeting is public, but a few Facts are known. One thing is that Hirohito bowed multiple times very deeply before MacArthur. This is in Japanese culture a powerful Sign. Hirohito said basically that the war was his fault and that he takes full responsibility for it. This surprised MacArthur since he thought that Hirohito would try to talk him out of responsibility. From this meeting came a famous Photograph. (You find it easily if you search for MacArthur Hirohito meeting.)
Later in his Life MacArthur stated, that Hirohito was the biggest gentleman he ever met.