I want them to hide in dark caves and holes in the earth, shivering with terror whenever they hear the roar of diesel engines because the tales of their ancestors talk about metal monsters crawling over the earth, spitting death and destruction.
I want their mothers to be able to admonish them with "If you don't behave, the Pale Destroyers will come for you", and that will be enough to reduce them to quivering obesience.
I want the annihilation to be so complete that their mythology will tell them of the day of judgment when the stern gods from across the sea .. the powerful 'Mericans .. destroyed their forefathers' wickedness.
Kill them all ... nits make lice.
(COL Chivington, Sand Creek)
And let the time be known as Dies Irae, the Days of Wrath.
but I must admonish you with humble heart & say "Be careful what you wish for"