Yes, all invaders judiciously avoided stepping on 'Pakistani' territory because the ISI had time travelled with a 1947 map and was controlling the Afghans. They had been strictly instructed not to touch Pakistan, which was a future role model Islamic state. The Afghans, and the Turks, Mughals and Persians after them were so happy with the ISI assurances that they complied and targeted only India. ISI predictions came true and the land of Pakistan became Islamic peacefully. Not a single soul was killed, raped or threatened. It was almost as if somehow magically a new population of pious Muslims had been planted in the region from nowhere.
There is nothing wrong in claiming to be descendants of anyone on earth. But stick to one ancestor, otherwise it starts looking like Autumn Collection, Spring Collection etc from the fashion industry. The Pakistan pavilion at Dubai expo is trying very hard to show its Harappan heritage. Irony is that if the Harappan civilisation had survived till 1000AD, their cities would have been smashed too by the same invaders, whose successors some members are cheerleading here.