[F]or Nichiren, the immanence of the buddha land was not merely a truth to be realized subjectively, in the practice of individuals; it would actually become manifest in the outer world as faith in the Lotus Sūtra spread. We have already seen how he saw the disasters of his age as stemming fundamentally from rejection of the Lotus Sūtra in favor of inferior, provisional teachings no longer suited to the age. Conversely, he taught that — because people and their environments are inseparable — spreading faith in the Lotus Sūtra would transform this world into an ideal buddha realm. He famously argued this claim in his treatise Risshō anokoku ron, written early in his career, and maintained it throughout life. This was the conviction that underlay his aggressive proselytizing and that prompted him to risk his life in repeated confrontations with the authorities.