Page:The Fall of Constantinople.djvu/154

 136 THE FALL OF CONSTANTINOPLE. which dynastic changes had been made, and the continual troubles which existed within the city, led the military leaders of the West to believe that she would be unable to resist a combined attack by land and sea. The crusades had thus not only largely contributed to the weakening of the empire, but they had shown that weakness to the West in a way which directly invited invasion.