Explain the concept of the iron curtain

This is what divided Europe into 2 separate areas from the war years of 1945-1991. After it ended the Soviet Union became dependant on the Eastern and central European allies.

Correct

A willingness to unify against an opposing ideology

Explanation:

In the passage below, the views expressed about trendsin European Christendom is about the willingness to unify against an opposing ideology. This could be seen in this quote below:

"For the love of God, we will add to the fleet fifty armed galleys on condition that, so long as we act in company, of all conquests in land or money, whether at sea or on dry ground, we shall have the half, and you the other half"

The knight was talking about the need for them to carry out their Crusade in agreement together rather than individually.