Thanks Tom
That was one of my points. These sorts of pronouncements are made to create the impression that al Qaeda is still active and functioning and to entice young, impressionable Islamic fundamentalists to join the "cause."
"Terrorism" is really just a bunch of small violent acts that have more political than military value to those perpetrating them. Even the World Trade Center disaster, as awful as that was, made scarcely a dent in the fabric of American culture and power. If there is any value in the Iraq war, it is reminding them of just that point.