Those who forget history are doomed to repeat it. Renaissance Europeans understood full well that Islam was incompatible with the values and culture of the West. They understood its vile aggressiveness and danger. If not for the titanic struggles at Lepanto, Vienna, Malta and Grenada, the Islamic wave would have destroyed Western culture. Today politically correct moral relativism has made Western culture again vulnerable to this bizarre threat. Massive Muslim immigration into what was once known as Christendom has been a catastrophe. 9/11 and Boston will not be the last atrocities Americans will suffer.
If by "Renaissance Europeans" you're speaking of the medieval Crusaders and what was left of the Holy Roman Empire in the 17th century, than yes.
I remember when "The Crusades" were despised around here, just like they are today in academia.
In an age in which we could use a Charles Martel, a Jan Sobieski or a Pius V, we get a Hilary Clinton, a John Kerry and a B. Hussein Obama.
This does not bode well for the future of the West.
You left out the Ft. Hood muslim massacre, which obama calls, "work place violence".