This says all I need to know:
“The Philippines has been grappling with incidents of terrorism, especially on the southern island of Mindanao. There, in the city of Marawi, government forces have been battling ISIS-linked militants for control of the city.”
I have known a number of Philippinos over the years, seemed to be all Catholic. Reading Wikipedia about Mindanao it seems what is occurring there is really just a continuance of 100 years of effort to push Muslims out.