Air traffic controllers in the dark on Sept. 11

At La Guardia, the tapes make clear, officials in the tower knew very little. Just after 9 a.m., shortly before the second plane hit the trade center, an unidentified woman in the La Guardia control tower spoke by phone with a Port Authority police officer, also unidentified on these transcripts.

'Do you know what happened at the World Trade Center?' the woman in the tower asked the policeman. 'Yeah, we ... we just got it from what we are getting on the news,' he responded. 'We are sending a whole bunch of people down there, just so you guys know. We think a plane crashed into it.'

'A plane crashed into it?' she asked.

'A plane crashed into the World Trade Center, yeah,' the officer said. The trade center's twin towers could be seen from the tower at La Guardia, and as smoke billowed from the north tower, one supervisor looked at Lower Manhattan through binoculars and saw the second plane circling around the towers, according to an aviation official.

At that moment, fighter jets from Otis Air Force Base in Massachusetts were racing toward the city and were about 71 miles, or 114 kilometers, from the trade center, eight minutes' flying time, according to testimony at a 9-11 Commission hearing.

Nothing on the tapes shows that the La Guardia controllers knew that the planes flying into their airspace had been seized by terrorists, or that military aircraft were screaming in pursuit over the Hudson River. Commercial airliners continued to line up at La Guardia for takeoff, the transcripts show, as the second hijacked plane plunged into the south tower of the trade center at 9:02 a.m. Four minutes later, the air traffic in the area was grounded.

At 9:07 a.m., a Federal Aviation Administration ground dispatcher contacted planes getting ready for departure. 'There's nobody that's going to be leaving La Guardia,' the dispatcher said. 'Everybody just stand by.'

The US response on 9/11 shows a pattern of isolated agencies which were neither communicating with each other nor getting any central direction from the president. The traditional no-one could have imagined defence has been proved untrue. The choices remain incompetence or negligence.