Bill Gertz of the Washington Times reports that al-Qaeda plans to assassinate a major "U.S. or foreign leader either in the United States or abroad." Furthermore, the attack would signal "attacks to follow involv[ing] 'multiple targets in multiple venues' across the United States."
In addition, Gertz reports:
"The goal of the next attack is twofold: to damage the U.S. economy and to undermine the U.S. election," the official said. "The view of al Qaeda is 'anybody but Bush.' "
The officials also said the terrorist group has begun using female members for preattack surveillance and possibly as suicide bombers, thinking that women will have an easier time getting past security checkpoints at airports, borders and ports.
One main target for the al-Qaedans is oil refineries. US refineries are operating at nearly 90% capacity. No new refinery has been built in the US since the mid-1970s according to the Energy Information Administration, a Department of Energy sub-agency, and the only thing maintaining processing capacity has been "capacity creep" -- adding new refining capacity to existing refineries. Nonetheless, the EIA states that "[s]ince 1988, the United States has lost over 1.6 MMBD of capacity, which is about 10% of today’s total refining capacity." Refinery capacity stats are available here. Why the lack of new refineries? Environmental protests -- any new refinery proposal is guaranteed to be tied up in litigation for a decade on NEPA, Clean Air Act, Endangered Species Act (there's always one in some proposed industrial area; two words: snail darter), Clean Water Act, etc. lawsuits
So some primary al-Qaeda targets are obvious and the impact of shutting down a refinery would be great. More importantly, certain refineries are the only ones to produce certain special gasoline formulations (i.e., for smoggy cities like Chicago and LA).
This is how al-Qaeda wants to damage this country and install ABB as president. The question is whether we will be unable to prevent that.
See also: Outside the Beltway for general comments;
Allahpundit for odds on who al-Qaeda wants to whack (although John Howard's not on his list, and Australia has an election coming up too).