Yet observers say the president's new offensive appears more precisely timed for the start of a fall election campaign in which the war in Iraq has become a pivotal issue in many congressional districts and Senate races and the Republican Party is struggling to maintain control of Congress.

John Mueller, a professor of political science and national security at Ohio State University who has studied the impact of casualties on public support for war, suggests that Bush is playing to his political strength with this new offensive but has passed the point of regaining support for the war in Iraq.

"It's his strongest suit, and terrifying people over terror can win votes for him and his party," Mueller said. "There is an election coming. Terrorism is his strongest suit. The standard thing in an election is to focus on your strongest suit."

Mueller cites the words of a 20th Century social critic, H.L. Mencken: "The whole aim of practical politics is to keep the populace alarmed."

Yet, "judging from polls," public support for the president's argument that the war in Iraq is the central front of the war on terror "is starting to wane," Mueller said. "I don't think they have any new arguments, so people may not pay much attention, because they've already heard this 400 times… What happens is, as people drop off, they tend to stay off."