If it's "almost impossible to raise achievement", then the implication is that the "leaking pipeline" in higher ed, where minorities drop out at a proportionate

If it's "almost impossible to raise achievement", then the implication is that the "leaking pipeline" in higher ed, where minorities drop out at a proportionately higher rate at each step, reflects an inherent difference in aptitude between different races. It would also mean that Americans are inherently "dumber" (loosely speaking) than Europeans, since they on average score lower on tests of math and science. After all, nothing can be done to raise achievement, so it must be inherent. I don't believe that for a minute. I also think the statement is empirically false; It is perfectly possible to raise achievement, and I think it's much more probable that the difficulties doing so on a large scale are rooted in flawed educational practices and cultural/societal factors.