The fact he's a terrorist makes everything he says questionable. That's the point I'm making, and without having some intimate connection with him, his absolute motives died with him
And you really should avoid trying to argue the notion rational thought
You have to put up with us as we are .
Sorry.
The reason for terrorism has to be considered.
People do atrocious things to get noticed and heard, this doesn't mean that they cannot also lie, but the message and the method are not totally separated.
His speeches and writings were justification to his followers to do the drastic acts, that drew the attention for the purpose of recruiting more fighters and supporters, as well as inspiration in telling them what to expect as results from all their efforts.
So one of the reasons for terrorism is theater , and dissemination of a message on the back of the terrorist acts.
Another reason for Terrorism is local and distant control of behavior. Local people are dismayed and cowed by the violence and become co-operative, supportive and cheerleading even. Distant people may change their behaviors also , depends on how awful it is and how the threat is directed and felt , I expect the distant effect is less than the local , this might be why some attacks were needed on our own soil.
Both reasons require that a message be given, to those you are recruiting, encouraging and asking for support you might lie , but it would have to be a lie that was consistent with the mission you were giving them, to those you are intimidating and threatening and coercing your message needs to be consistent with the behavior you want of them even if it need not be the whole truth.