Well, it's the motive behind any atrocity committed during war, what's a few cracked eggs if there is a grand goal in mind. There are always people in places who feel like it's a historical duty to carry out those plans. And the war crimes stay in the past and get forgotten but nobody can deny the new reality on the ground. You can ethnically cleanse an area and in a 100 years that becomes barely a historical footnote and a new reality emerges and nobody can dispute that the area is occupied by a nation that claims rights based on self determination. Same for settler colonialism, they're not invading, just changing the actual conditions as a precursor to claiming political legitimacy.