The UK has fallen victim to drones, chemical weapons and cyber-attacks in recent years. But at least it's got a really big boat.
Cheap, powerful, and more widely used by greater numbers of people, drones are causing a headache at supposedly secure locations worldwide.
Both Goldsmith and Khan oppose the Heathrow expansion – so how will they solve the air capacity crisis?
The key consideration for a new airport is ultimately market demand – what do customers want. And airport customers (airlines) want a Heathrow hub.