Nichiren Daishonin states in “Rissho ankoku-ron”:
When I, with my limited knowledge, read the sutras, I find that all people have gone against the correct Law and become wholly devoted to evil doctrines. This is why all the guardian deities have abandoned this country and sages have left this land, and not to return. Seizing this opportunity, devils and demons rush in, bringing disasters and calamities. This is most fearful. We must speak out!