Interplanetary war

In 2006, Earth's first interplanetary war was anticipated as the British government requested that the United Nations provide access codes for nuclear weapons against an alien threat. In reality, this was a Slitheen plot to destroy the Earth for profit, which was thwarted by the Ninth Doctor. (TV: World War Three)

Over the 50 years after sending a rocket to the planet Mechanus, Earth became involved in interplanetary wars, with Steven Taylor cited the Human-Draconian War, the Second Dalek War and the Third Dalek War as factors which put an end to Earth's expansionist phase, leaving planets like Mechanus uncolonised. (PROSE: The Chase)