Last month I attended an international lecture by one of Japanology's senior scholars. I'll call him Dr. Frink. Decorated by the Japanese government for his contributions to the field, he talked about Japan as a "unique" state that never really changes, even as it slips to third place behind China's economy.
One reason he gave for this was that "Japan is still the most homogeneous society in the world." He defined homogeneity by citing Japan's tiny percentage of resident foreigners.
That was easily disputed after a quick Google search (the lecture hall had Internet; welcome to the 21st century). I raised my hand afterwards and pointed out that some 60 countries were technically "more homogeneous" than Japan, as they have smaller percentages of foreigners, foreign-born residents and immigrants.