There are things they can do, and things they should do, and there are things they won’t do.
Japan is working with Chinese nationalities and with the Koreans and with the Philippines because they really have no fear of Christianity, they are even looking at novel ways of bringing their own birthrate up. Some of the solutions being talked about are actually quite cute.
But the biggest of the things they WON’T do, is allow Muslims unfettered access to Japan
But this is Japan, and it will stay Japan.
Nihon-arabia is NOT going to happen.
In that regard, (JAPAN IS) probably only one of the few places left on the planet that is hermetically sealed against Islamofascist terrorism and were they somehow to strike here (which would be in a limited way), you would not see a scraggly beard nor a prayer rug nor a burqa in this archipelago from Wakkanai to Naha for 500 years to come. They would all be rounded up, legal and illegal resident alike, and shipped back to Mecca without so much as an onigiri roll and a can of Pocari Sweat.