Actually, that's not quite right. They got out of the competent war making business then. That's not to say their penchant for lethal brawling abated in the slightest.
This is one of the reasons why a criminal like Saddam Hussein found it so easy to take over and oppress the Iraqi people.
The Arabs have not had a reputation for successful, or serious, war-making for over 1,000 years!
It's worth noting that the great Christian Crusades to take back the Holyland started with the Arab administrator of Egypt literally requesting European Christian assistance in breaking the Seljuk Turk blockade of the pilgrim (tourist) business!
In the end the Crusaders were evicted from the Holyland by a Kurd named Sal Al Din.
It's disengenuous for an Arab punk like Usama Bin Laden to express concern about the Crusades. Simply proves he doesn't know Arab history, or he does but knows that people in the West have forgotten and don't care!