

Note that I said the fall of Rome, not of the Empire.  The Roman Empire
lasted until 1453, with its transfered capital in Constantinople.  The
main reason for it's fall was not so much the sack of Constantinople by
the men of the 4th Crusade (who were not Christians - they had been
excommunicated down to the last man after attacking the Christian city
of Zara in Croatia), but rather the disastorous defeat in the battle of
Mazinkert.  After the Turks breached the frontier, it was only a matter
of time before the Empire fell, the inability of the Empire to hold onto
the rim of Anatolia, with the Ottomans and Rum Seljuks in the middle
should be quite obvious to any student of history.  The sack of
Constantinople only hastened the inevitable along.  For if the Greeks
had wanted to save their empire, why would they not cooperate with the
Crusaders when they came to do battle with the Saracens in the 1st-3rd
Crusades?  Because of their obstinacy over cooperating with people they
considered heretics, even though those "heretics" were fighting for the
cause of the Empire and Christendom in doing battle with the Turkish
hordes in Anatolia, Edessa, Lebanon, Palastine, and Syria, the some
hordes who were to later sack Constantinople, and overrun a third of
Europe (the Balkans, Hungary, the Ukraine, the Caucasus, etc.)