The Thernstroms prescribe little to end the harms wrought by past injustices, or even to fight latent racism--except stopping affirmative action and kindred policies.
The Thernstroms have another, as yet unknown, effect that is important. 
mnli hypothesis: The Thernstroms have another, as yet unknown, effect that is important.  premise: The Thernstroms prescribe little to end the harms wrought by past injustices, or even to fight latent racism--except stopping affirmative action and kindred policies.