The continuing argument you got a piece of from your fellow-discussant is an interesting one, but somewhat different from the arguments that roil ACW threads.
For one thing, the argument you encountered is one I've never heard in 50 years of paying attention to affairs in the "Muddle East" but which may have been current in Arab and Arabophile circles for a long time. The Arabs specialize in outre' theorizing, speculation, and canard-generation as a substitute for rational discussion. They have no use for rationality, in fact, since argumentation serves a completely different function in their culture. They don't care about truth, as we understand it. To them, truth is about upholding the family, tribe, nation, Umma -- and about cashing in and making good various claims presented under the rules of vendetta. It isn't that justice and fact-finding are alien to them, it's that group loyalties count for much, much more than mere facts. In the Arab-Israeli conflict, the destruction of Israel and the Jews is the truth, and anything that impedes that truth is a lie, a canard, a base personal insult to the intelligence and humanity of every person who whom it is offered.
I say that in all existential humility, yielding to the better insights offered by people like Bernard Lewis and Fuad Ajami, who try to educate the rest of us. Because one feature of Middle Eastern argumentation, among the Arabs especially, is obfuscation and confusion: they don't want to know your truth, or any objective or objectifying truth, and more importantly, they don't want you to know it either, so they obfuscate and lie continually, to protect the "truth-telling" and claim-presentation processes of their own dysfunctional society.
As far as I can tell.
Which is why, for example, multiple canards, and canards based on completely different lines of logic, are tolerated simultaneously, for their operational value in confusing and disinforming you. So the canard about Gamal Nasser's "real motivation" may have been around for years and quite current in Arab society, and now it is uttered to you, to disinform your understanding of the history of the Six-Day War.
IMHO.
For me, the Western narrative is straightforward and truthful. You're right, the Israelis struck first after detecting numerous fatwas and gross death-proclamations against them, and I know of nobody in the West, other than case-hardened, often white-shoe "Arabist" antisemites and their more recent Leftist supporters, who has professed to disbelieve that narrative.
Substitute North and South and that is exactly what is happening on these threads and has been for the last 7 years.
Truth is a huge casualty in all the discussions over the war for not many are really interested in it. The agenda here is to make sure one side remains untarnished and the other side remains unburnished. That is what all the spinning, lying, and disseminating is about. It is the only game being played out on these threads.
And when called on it... either side... then the howls and insincere protests of innocence begins.
Agenda and not truth. That is the only way most can carry on their campaign against the other side with a straight face.