Every time he does, China and Korea, which suffered atrocities at the hands of those war criminals, do things like call off official visits, raising tensions all over the Asian Pacific.
And it's not like those war criminals are enshrined in the sense of being part of a blanket enshrinement of all war dead. Their names are actually listed in the shrines "book of souls." Not only that, they are listed in there as martyrs.
More on this in another post.