'Audacious' - This was the word used repeatedly to describe the attack carried out by Ukraine deep inside Russia, targeting the Kremlin's nuclear-capable long-range bombers.

Drones smuggled into Russia in lorries struck at least four air bases simultaneously - one base was in Siberia, which is a long long way from Ukraine. The mission was called Operation Spiders Web, and it seemed we were watching the future of warfare play out on our screens. 

In the past 24 hours, Russia has responded by carrying out large-scale drone and missile strikes on Ukraine's capital, Kyiv.