And those who disbelieve are allies of one another, (and) if you (Muslims of the whole world collectively) do not do so [i.e. become allies, as one united block under one Khalifah (a chief Muslim ruler for the whole Muslim world) to make victorious Allâh’s religion of Islâmic Monotheism], there will be Fitnah (wars, battles, polytheism) and oppression on the earth, and a great mischief and corruption (appearance of polytheism).1
— Muhammad Taqi-ud-Din al-Hilali & Muhammad Muhsin Khan