I read the Meacher peice in the Guardian and he seems to be saying that, while the war against terror may be legitimate, there were already plans in place to attack Afganistan and establish a strong military prescence in the gulf states well before the events of Sep11.
He also suggests that at least 11 countries had provided advance warnings of the attack and that some specific details were known. The inference of this is that Bush was inviting an attack to give him the moral high-ground while pushing through those plans.
It would be hard to imagine that anyone could accept the tragedy that occured as part of a game plan but when serious political figures start making these kind of statements in the national press it does make you wonder.