""Are the Crusades destined to happen all over again?""
Good example. The Christian Kingdoms each time responded to a Muslim Invasion and Conquest. Should we have laid down and died?
As an example, the Reconquista, or the invasion of the Moors (Muslims) in Spain. If the Christian Kingdoms did not respond to the Muslin Invasion of Spain, Spain would not exist as we know it today. The Crusades slowed and stopped/repelled in most cases, the Muslim onslaught in Western Europe.
If you are relying on JW propaganda regarding the Crusades, try reading some History on your own. A good book is "A Concise History of the Crusades" by Thomas Madden
Regarding the Native Indians, I too, feel regret on how Humans have trampled Humans. However, the reality of life is that you cannot name one Nation that has not been invaded at one time or another, with people displaced. It is a fact.
As world Powers go, the US is the most benevolent world power in History. We could of had it all after WWII, instead we help build Nations to even greater prosperity (Japan, Germany). What other world power of the past would have done this? Where is the context?