This all happened 600 years ago across Europe. The result was Islam was outlawed and the Muslims (Muslim invaders, forced converts and their descendants) were required to convert to Christianity or leave.
This implies that they can know who’s Muslim. At the least this would keep it underground.
Angola (who might be a communist country, I’m unsure) is very restrictive on Islam as well.
Heck, there is a semi-moratorium against Jehovah’s witnesses in some Russian cities it seems and they aren’t even a tad violent.
Those claims about Japan are false.
Unfortunately that Japan graphic isn’t true and has been debunked.
I don’t know of a “University of Japan”, but in the foreign language schools of Japan, be it in Osaka ( OSAKA GAIDAI ) or Tokyo ( TOKYO GAIDAI ), ARABIC and PERSIAN are both taught if students want to major in these languages.
I know, I was a student for 9 months in Osaka Gaidai.
It is NOT TRUE that Muslims cannot rent a house in Japan ( if by “house” you mean something that has a lot as well ).
There are MANY Muslim students in Japan. I met a lot of them when I was a student there — Pakistani, Egyptian, Persian, even Arabic.
There is also no truth to the claim that that you cannot import a Koran into Japan. There are several mosques operating in Japan.
SEE HERE:
http://japanfocus.org/-Kawakami-Yasunori/2436/article.html
At the mosque in Ebina, Kanagawa Prefecture, about 10 children around age 10 are learning the Arabic alphabet. Every day from 4 pm to 8 pm, the mosque holds Koran classes. They started last November, at the urging of Pakistani and Bangladeshi Muslims living in the area who wanted their children to be properly versed in the ancestral religion and the Arabic language. The classes are taught by the parents themselves.
Finally, regarding embassies, Japanese Ministry of Foreign Affairs maintains embassies in several predominantly Islamic countries, including Afghanistan, Albania, Algeria, Azerbaijan, Bahrain, Bangladesh, Comoros, and Egypt.
SEE HERE:
http://www.mofa.go.jp/about/emb_cons/protocol/a-h.html