The USA's Transportation Security Administration or TSA has said that the new rules - at least insofar as they relate to what happens on an aircraft - are now to be regarded as a matter for the discretion of the crew.

That's both good and bad.

It's good because long-haul crews were facing the ridiculous situation where they were unable to deliver their meals service at the appropriate time. Why? Because the last hour of a flight is when everyone, having eaten and had drinks goes for a pee, a wash and a shave, or whatever. It's when they unstiffen themselves. In short, the last hour is when the crew tidy up and the passengers move around. Push service back an hour and passengers have eaten too early and been woken too soon. Push service on an hour, and passengers will be crowding the toilets when the plane is on the ground.

It's bad because it places the onus on the crew in a role that is quite simply not their job.

But crews are saying that they don't know what to do: the TSA's latest version has not been fully disseminated and considered by airlines and so no changes in instruction have been issued.

The TSA issued a bland statement on 27th December. It all sounded remarkably innocuous. It wasn't.

"Q: What additional security measures are being taken for international flights to U.S. destinations?A: TSA issued a directive for additional security measures to be implemented for last point of departure international flights to the United States. Passengers flying into the United States from abroad can expect to see additional security measures at international airports such as increased gate screening including pat-downs and bag searches. During flight, passengers may be asked to follow flight crew instructions, such as stowing personal items, turning off electronic equipment and remaining seated during certain portions of the flight.

Q: Do passengers need to do anything differently to prepare for checkpoint security procedures? Has anything changed in terms of what passengers can bring in their carry-on or checked bags?A: At this time, security checkpoint requirements for passengers departing U.S. airports remain the same. Passengers do not need to do anything differently, but they may notice additional security measures at the airport.

Q: Should passengers plan to arrive at airports earlier than normal?A: Passengers travelling within the United States should give themselves extra time to check in and proceed through the security checkpoint before their flight, especially during the busy holiday travel season. TSA advises that passengers travelling on international flights to U.S. destinations allow extra time for security and arrive an additional hour earlier."

Behind it was a raft of measures that caused delay, annoyance and discomfort to passengers. And basically told the rest of the world where to go: "The American people should continue their planned holiday travel." The implication that the rest of the world should stay at home is clear.

But the success of the TSA and the Department of Homeland Security is open to question:in the week 14/12/09 to 21/12/09, the two agencies combined found the following:

• 21 passengers were arrested after investigations of suspicious behaviour or fraudulent travel documents
• 37 firearms found at checkpoints
• 3 artfully concealed prohibited items found at checkpoints
• 37 incidents that involved a checkpoint closure, terminal evacuation or sterile area breach

The 37 firearms is disturbing - but not disturbing enough for the US government to do anything about the ubiquitous carrying of weapons by Americans. And the term "checkpoints" includes physical border crossings including the Mexican border.

Only three "artfully concealed prohibited items." That includes cash smuggling which the USA has convinced the world is as big an evil as terrorism.

Suspicious behaviour? How is that defined. The USA claims big success for its system for spotting potentially dangerous people from their behaviour. But one of our own staff was recently threatened with arrest at London's Heathrow airport when a "pat down" turned to a fondling of his genitals and he told the man doing it to f*** off. No doubt the Americans would have viewed that as suspicious.

And the TSA admit that airport security is not foolproof at US airports: in July this year, a passenger stuffed a can of mace up his bum. He took off his shoes to pass security, and the scanners did not identify the threat. In fact, it was found only because he ran (barefoot because his shoes were in an X ray box) to the nearest toilet to, er, "recover" the can and - because he was an idiot - he carried it out of the toilet with him and started to look for a waste bin to put it in. Was he arrested? No - in fact, he was allowed to change to a later flight. But he missed that one, too, because he turned up at the checkpoint with a bottle of lighter fluid in his hand.

The TSA said "Passengers flying from international locations to U.S. destinations may notice additional security measures in place. These measures are designed to be unpredictable, so passengers should not expect to see the same thing everywhere."

US President Obama has waded into the discussion, and that bodes ill for long haul travellers worldwide. But his first criticisms have been for domestic agencies who he says failed to respond to so-called "red flags" relating to the flying idiot who set fire to himself and is alleged to be a terrorist.

""There was a mix of human and systemic failures that contributed to this potential catastrophic breach of security," said Obama.

He's both right - and wrong. 23 year old Umar Farouk Abdulmutallab was named on a primary security list. Even though, according to US government sources, his own father tried to warn US officials that his son was up to no good, he was not elevated to a formal watch list and certainly not to any "no fly" lists.

Also, there are reports that the US authorities had access to conversations between the suspect and known al-Qaeda persons.

At Amsterdam Airport, the substances he carried did not show up on the scanners in use there, yet Amsterdam has some of the most advanced scanners in the world. It also has "back-scatter" scanners - electronic strip searches - but the EU has told the airport operators that the results are a breach of human rights and they cannot be used. There are however, reports that Schipol may decide to use the "full body" scanners for US bound flights anyway.

In the meantime, and back to the original point, just after the new rules were put in place, a passenger on the same flight, Northwest 253 from Amsterdam to Detroit, was taken ill shortly before landing. He went to the toilet and had to stay there due to his condition. The crew kept telling him he had to return to his seat; his body told him otherwise. Eventually, he yelled at them, crudely telling them to leave him alone. He was arrested until someone noticed his condition and at last listened to what he was telling them. Then they announced he was not a threat. Seemingly, no one apologised to him.