So if Mussolini said it, it must be true?
Mussolini used religion, not independent thinking spirituality to con his Italian citizens. He actually had been an unabashed anti-cleric, anti-Catholic atheist, but it became clear to him that in order to ascend politically he had to do so within the existing social order.
Mussolini adapted by working within the constructs of theological hierarchy — marrying in the church, baptizing his children there and in his first parliamentary speech in 1921 announced that “the only universal values that radiate from Rome are those of the Vatican.”
Historically, authoritarian leaders on both the right and left are generally not spiritual or religious. More often to the contrary. But intuitively they understand the need to coalesce with prevailing religious institutions and thought. And why not? The elements for authoritarianism alignment are already in place: a centralized power structure, obedience to authority, belief in one set of inerrant teachings and mistrust of outsiders who are not members of the faith, political party, or culture, among other reasons.
Those with mystical leanings— such as the celebrated names I mentioned in a previous post that you never addressed— demonstrated a non-institutionalized spiritual seeking or “spiritual questing,” an antidote to fascism or authoritarianism of any kind.