Yes he is drawing an equivalence between Muslim terror today, and what happened in medieval Europe. That’s exactly what he is saying. And he is saying we can’t condemn Muslim terror because of what happened in medieval Europe centuries ago.
What happened in Medieval Europe was completely justified under the Church’s “just war” theory.
The Seljuk Turks were the ISIS of their day. They were rampaging across independent (Christian) lands, raping, murdering and forcing conversions. They had been at War with Orthodox Byzantium for a century already, and had won enough victories they were becoming a threat to Western Europe.
The ole Oke Doke. Liberal moral equivalence. The west should therefore, be forever paralyzed.