The Crusades failed because the Crusaders committed genocide against Jews, Orthodox Christians, and Muslims. Also, the sleeping lions of Islam were awaken to answer the call of defensive Jihad on behalf of the protected peoples "Dhimmi" (Jews & Orthodox Christians) and the Muslims.
However, the Crusades (in Jerusalem and Al-Andalus) resulted in the ideas of Islamic Civilization being passed on to Europe, which created the Renaissance and later the USA. Also, the Templars due to their heavy influence of Islam on their return to Europe were banned by the Catholic Church and sent underground with secret societies such as the Freemasons which passed on the spiritual message of Islam through Freemasonry. This of course resulted in the creation of the United States of America later in history based on Freemasonic (Islamic, Christians, and Jewish) esotericism. Freemasonry teaches "The Fatherhood of God (Allah) and the (Muslim Brotherhood: Submitter to God's peace and harmony in brotherhood with humankind) brotherhood of man".
Basically, our founding fathers in the USA created the United States on a foundation that is based on Islamic, Jewish, and Christian esoterics. That is why I find it ironically funny when right wing fanatics here say that the USA was founded on Christianity. It was actually the multicultural and perennial philosophy in Islam that helped make America what it is, which again that same multiculturalism is under threat by the right wing neo-crusaders.
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