Memo to the British Airport Authority: I would rather be exposed to the threat of terrorism than fly without my water and my book.

While the draconian restrictions on carry-on luggage have been relaxed in recent days (liquids are still verboten, laptops and reading materials are allowed), the threat to our freedom to travel in peace has not... At what point does discomfort outweigh a seemingly random threat to public safety?

Cars are hugely dangerous both to our physical well-being and the environment, yet most of us continue to travel in them. Why? Because to do otherwise would be incredibly inconvenient. Almost as inconvenient as an international flight without Evian and the latest bestseller.

This is not simply an issue of entertainment or hydration. It is a matter of sanity.