Christianity and the Destruction of the Peoples of Canaan

Hey Miki
I shared my insights on the role of progressive Judaism with M. from Tirat Zvi [son of my ex-partner].
And in the process, it occurred to me that since Christians see themselves as the heirs of the people of Israel, perhaps they adopted the commandment to destroy the peoples of Canaan as a source of legitimacy for the destruction of all kinds of infidels, [so they can live in peace with the commandment of compassion that is supposed to characterize Christianity…]
M. argued against me that the Christians did not need the aforementioned commandment, because they were the heirs of the Roman Empire, which was known for its belligerence.
And in its unbridled cruelty.
Then I remembered David Naim, a singer of Israel, who commanded:
He went to Moab and measured them with a line, laid them on the ground, and measured two lines to the east, and the full line to the west…
And Amaziah king of Judah fought against Edom, and the children of Judah captured ten thousand men alive, and brought them to the top of the rock, and threw them down from the top of the rock, and they all died.

So Christians definitely had the opportunity to learn cruelty from us…
I would love to know if you have any comments or insights on this topic.
All the best