Notice the tone of this memo, its doesn't sound like they are saying that if a terrorist attack happens, it will be good for the President's popularity rating, but it sounds more like if we orchestrate a terrorist attack...

http://www.capitolhillblue.com/artman/publish/article_7639.shtml

A confidential memo circulating among senior Republican leaders suggests that a new attack by terrorists on U.S. soil could reverse the sagging fortunes of President George W. Bush as well as the GOP and "restore his image as a leader of the American people."

The closely-guarded memo lays out a list of scenarios to bring the Republican party back from the political brink, including a devastating attack by terrorists that could “validate” the President’s war on terror and allow Bush to “unite the country” in a “time of national shock and sorrow.”

The memo says such a reversal in the President's fortunes could keep the party from losing control of Congress in the 2006 midterm elections.

GOP insiders who have seen the memo admit it’s a risky strategy and point out that such scenarios are “blue sky thinking” that often occurs in political planning sessions.

“The President’s popularity was at an all-time high following the 9/11 attacks,” admits one aide. “Americans band together at a time of crisis.”
...
The memo outlines other scenarios, including:

• Capture of Osama bin Laden (or proof that he is dead);
• A drastic turnaround in the economy;
• A "successful resolution" of the Iraq war.

...