| Complex subject, caught between drama and journalism
This film is a "realistic" dramatisation of a future documentary about a major day of transportation disasters in Britain. It is based to some extent on fact: massive overcrowding on roads, train strikes on the grounds of "safety" causing danger to the traveling public and a creaky air traffic control infrastructure. Some elements of the scenario have actually "more or less" happened, such as the roads grinding to a halt as a result of strikes, weather and accidents coinciding.
The piece is gripping from start to finish, in the compulsive way watching 24 hour news during a war is gripping. Morbid fascination takes over.
However, the subject matter is hugely complex. Assessing transportation risk and therefore deciding what to do about it, which path of action is the lesser of evils, is beyond the scope of a journalistic drama such as this. You are left worrying that it could all go horribly wrong, yet the more obvious steps the government might take could well be counter-productive.
Conclusions such as "it's the fault of the system, not the individuals within the system" are valid up to a point but unhelpful.
People interested in this subject might gain more from reading books such as Risk by John Adams or the superb paper on how unintended consequences of risk management led to the Valuejet Air Disaster (I don't have the reference to hand but I have the paper somewhere).