You are the second person to use that damn statement. Where the hell does it come from ? Church ?
Anywho, Genius often comes from the oddest of places, and by pursuing Eugenics, we'd lessen our chances of benefiting from it wouldn't we ?
The main selling point against Eugenics came with the fact that people are vain and only care for themselves. Hence, Oddities such as lazy/off center eyes, and facial structure, will be discouraged, and people will want designer babies, naturally only the rich will afford and manipulate it.
If Genetic engineering allows for an engineering of intelligence in addition to superficial features, then a select group will be able to control others. Concentrated power is the enemy of justice. Even though anyone with Intelligence will see what is wrong with the status quo, to rely on those people who are a product of the genetic advances to repudiate them is a bit far fetched.