Now Americans are back in front of their TV screens. Almost two thirds of them are more likely to watch news updates in the next few weeks, according to a poll released yesterday by the ad-buying firm Initiative Media and conducted over the weekend.

The trouble is that in two weeks since the terror attacks they have had nothing particularly captivating to watch. This is a real concern for the Bush administration. Nothing is ever going to match the horrific drama of the bombing and then collapse of the towers of the World Trade Centre. But none the less the need to mediate if not satiate the American public's considerable desire for revenge demands that the White House provides some evidence for public consumption that they are doing something to respond to the assault. This is not just a war Bush must win in the air, from the sea, on the ground, or wherever else the US military might seek to fight. It is also one he must win on the television screens if he is going to keep the public with him.

"Ever since Vietnam, American war planners have been acutely aware that you could not engage in a military conflict without dealing with and sometimes resisting the demands of the major media outlets," says Howard Kurtz, the media correspondent for the Washington Post.

The pressure is on to produce not only military results but results that are going to translate into powerful images that work at home. "We live in an instant gratification society in America," says Mark McKinnon, Bush's media adviser. "I think that's going to be one of the challenges. This is not a situation, I believe, in which you can provide instant gratification. But I think it's going to modulate. The instant retaliation moment is going to diminish. That is the administration's sincere hope." So far Bush has been successful.

The message from the White House has been to consistently dampen down expectations of a quick or immediately decisive response. "This is not Pearl Harbour," says national security adviser, Condoleeza Rice. "There are no beaches to storm and islands to take... [this will be] a war of will and mind." So far they have been successful. At 89% Bush has the highest approval rating of any president in history. The only former leader who even came close was his father, when the nation was at war in the Gulf. But the president knows only too well how fragile such a standing can be. A year and a half after his father enjoyed such popularity he had been voted out of office by a draft-dodger.

The concern is that if the military response does not come soon the public might begin to show signs of frustration.

"When the US loses what may be more than 6,000 people, there has to be reaction so that the world clearly knows that things have changed," said Newt Gingrich, the former leader of the House of representatives following a meeting of the Pentagon's defence policy board.

The White House strategy so far is to feed the media a regular diet of press conferences from key figures within the administration. "The Bush administration seems very aware of the importance of daily news coverage to get its message out. On a single day you'll see Bush, Rumsfield, Powell and Rice. They're all staged to aim the message of the day against Osama bin Laden," says one Washington insider. The trouble is that, thanks to the power of satellite television, the pressure is even greater. For with the schedule cleared to cover the crisis and 24 hours to fill, any incremental development soon has a momentum of its own. They are not just fighting to control the agenda of the day, but to keep ahead of the agenda for the hour.

Kurtz believes the administration has done enough not to have to resort to a cheap televisual stunt. "I don't believe that Bush needs some huge visual of many people dying in order to match the powerful image of the World Trade Centre collapsing," he says. "He has conditioned the American public not to expect an Iraq-style bombing. At the same time he needs to show that he's doing something."

This has produced some peculiar moments of choreographed collusion between the administration and the networks to convince viewers that things are happening when they are not. A CNN correspondent stands outside the perimeter fence at Barksdale airforce base in Louisiana telling us that: "Two B-52s took off about two hours ago and they have not come back yet."

Elsewhere, the CNN meteorologist tells us that there are some low-pressure clouds over the Indian ocean which could make life difficult for the USS Enterprise.

Immediately after the attacks an aircraft carrier moved in. The Pentagon said it was there to defend the eastern seaboard, but for media purposes it was a sign that something/anything was happening.

In the absence of images there has been rhetoric. The war, the administration points out, will come in two stages. The second phase, the global war against terrorism, is unclear. The objectives are fuzzy, the scope is sprawling and the enemy is both everywhere and nowhere at all. It is essentially a conceptual war, confusing for pundits and bad for television. The first stage, which involves the manhunt for Osama bin Laden and the bombing of the Taliban, bears all the hallmarks of a western. An enemy is on the loose and America is going to track him down. Bush wants Bin Laden "dead or alive"; he has told him that he can run but he can't hide. "Bush is not comfortable with the role of griever, but he is comfortable with the role of sheriff," says presidency scholar, Martha Joynt Kumar of Towson University. The trouble is we are not sure of the ending.

"All this military build-up for one man. The Americans are making him famous; imagine if you don't get him," says a senior member of the Arab League.

The precedents are not good. The last time the American military targeted Bin Laden, following the US embassy bombings in 1998, the images were poor. A crushed tent in the Afghan desert in Kandahar and a destroyed pharmaceutical factory in Khartoum, Sudan.

Worse still, Bin Laden had escaped, civilians were killed, mosques were hit and it turned out that the factory did not make chemical weapons at all.

"There's a feeling that we've got to do something that counts," said one participant at a meeting in the Pentagon. "Bombing some caves is not something that counts."