I am exploring an alternative history of a timeline if the centre of the British Empire is wiped off the map in the early 20th century.
The Tunguska event was believed to be an air burst comet or asteroid that occurred over Siberia, Russia in 1908.
In an alternate Earth-world, this event occurred over London at a time when Parliament was in full session, the destruction of London is total as it is across much of southern England, damage is even recorded in Edinburgh, Dublin and Paris - wiping out the British Parliament in session, the Monarchy and the centre of the British Empire.
What effect would this have had in the immediate aftermath and on the events or outcome of an alternate World War I in Europe and World?