Considering they aren’t christian, it sounds like a poor choice of words.. Maybe he meant well..
There are actually quite a few Christians in Japan. There are a number of monasteries, shrines, and Catholic Churches. Remember that Christian missionaries reached Japan in the seventeenth century and even then were making converts. I’ve seen some pictures of Japanese earthquake victims praying in utter misery, clutching a rosary. So not everybody there is without the love of Christ.