If there were a rule book setting out how to handle a disaster that has claimed hundreds of innocent lives, Egypt and Russia contrived to ignore every page.
Nowadays, information is instant, as everyone, including governments of the most recalcitrant nations, knows. Within minutes of the Airbus 321, which was being flown by the small Russian airline Kogalymavia from the resort of Sharm el-Sheikh to St Petersburg, falling out of the sky, the internet's flight-tracking tools revealed to the world its last moments: a line heading north-east from Egypt's premier seaside resort before straightening and aiming for the Mediterranean. Then, at a mid-point above the Sinai peninsula, as it flew over the villages at the centre of an increasingly vicious insurgency by Isis militants, the line stopped.
At this point, the rule book would state, the authorities should alert the public to the plane's disappearance and say the matter is being investigated. Officials in the aviation industry are trained to assure the relatives of passengers and all of us for whom flying is a regular activity that they know what they are doing. They make sure that they say what they can be certain of, say the same thing, and above all do not spread confusion and distrust by passing on rumours and their own individual theories as fact.
On Saturday, however, within minutes of the disaster, contradictory stories were emerging from the Egyptian aviation authorities. The plane had safely exited Egyptian air space, one official said. Another gave a detailed description of how the plane's pilot had reported problems with the radio system and requested permission to make an emergency landing at any appropriate airfield; that information was later denied, without any explanation of how such a detailed story came to be invented.
Above all, both the Egyptian and Russian authorities immediately ruled out any link to terrorism, despite the plane flying over a jihadi hotspot and the Russians being the latest bogeyman for Arab militants, thanks to their bombing campaign in Syria. As one Arab former pilot told The Daily Telegraph, the only reason you rule something out before you have studied whether it is likely or not is because you fear it is true.
The effect on Egypt's tourism industry, once a tenth of its economy but now reeling from five years of unrest, would be catastrophic if Sharm el-Sheikh - its one remaining bright spot - and the planes needed to get tourists there, were seen as no longer safe. We don't yet know for sure what happened; sabotage is possible, as is an onboard bomb; but so is mechanical failure, or human error, though the lack of any Mayday call - contrary to the initial report - would suggest a catastrophic failure.
The great problem now is that having made a very concrete assertion on the basis of what everyone could see was little to no evidence, the authorities will struggle to be believed even when they do have a definitive answer. However, even if Isil's involvement is ruled out, there is still a connection, in my view, to the terror campaign that Egypt faces, and the terrorism problem in the Middle East in general. These arise ultimately from the failure of local states to be accountable to their populations for what they do and say.
The sort of mixed messages we saw from Egypt on Saturday come about because lines of authority and responsibility become blurred in decades of dictatorship. One of the curious features of reporting on Egypt, where I was based for three years, is the surfeit of information made available to reporters by a system of government that is notoriously unresponsive to journalists' needs.
Trying to find a well-briefed departmental spokesman who will take phone calls is well-nigh impossible. A mobile number provided by a friend of a friend will often be picked up by someone who is equally likely to speak their mind, whether they are a minister or a janitor. It is usually impossible to tell whether they deserve to be as confident of their facts as they make out. Most often, they are driven not by the facts, but by panic. In systems like the Arab world's dictatorships, it is more important to be politically correct than accurate.
On Saturday, the pre-eminent need in Cairo was clearly to prevent the idea circulating that jihadism in the Sinai was out of control. The need in Russia was to limit the idea that ordinary holiday-makers could have suffered blowback from President Vladimir Putin's adventures in Syria.
The concern of officials is understandable; it is the refusal to consider that truthfulness is a value that is the flaw.
And as we have seen over the past five years of wild statements from rulers as they are challenged and overthrown across the region, it is governments which are most threatened by the failure to face up to reality.