Does he mean eugenics like these?
Deut. 7:1 - When the LORD thy God shall bring thee into the land whither thou goest to possess it, and hath cast out many nations before thee, the Hittites, and the Girgashites, and the Amorites, and the Canaanites, and the Perizzites, and the Hivites, and the Jebusites, seven nations greater and mightier than thou;
7:2 And when the LORD thy God shall deliver them before thee; thou shalt smite them, [and] utterly destroy them; thou shalt make no covenant with them, nor shew mercy unto them:
7:3 Neither shalt thou make marriages with them; thy daughter thou shalt not give unto his son, nor his daughter shalt thou take unto thy son.
Or,
Deut 20:13 - And when the LORD thy God hath delivered it into thine hands, thou shalt smite every male thereof with the edge of the sword:
20:14 But the women, and the little ones, and the cattle, and all that is in the city, [even] all the spoil thereof, shalt thou take unto thyself; and thou shalt eat the spoil of thine enemies, which the LORD thy God hath given thee.
20:15 Thus shalt thou do unto all the cities [which are] very far off from thee, which [are] not of the cities of these nations.
20:16 But of the cities of these people, which the LORD thy God doth give thee [for] an inheritance, thou shalt save alive nothing that breatheth:
20:17 But thou shalt utterly destroy them; [namely], the Hittites, and the Amorites, the Canaanites, and the Perizzites, the Hivites, and the Jebusites; as the LORD thy God hath commanded thee:
