Is equality of opportunity worth it?

Ezra Klein blogs that "No one really believes in ‘equality of opportunity’," and goes on to suggest that equality of outcome and equality of opportunity are inseparable: "You can’t have real equality of opportunity without equality of outcome." His argument is that truly leveling the playing field in terms of the life chances of kids would require providing kids with poor parents the same start in life as kids with rich parents, and that would require providing them with... rich parents!

Well, that's not necessarily correct, as John Roemer has argued. One could imagine an equal opportunity policy regime in which the government provided compensatory assistance to kids from disadvantaged backgrounds, to the extent that a poor kid who worked just as hard to succeed as a rich kid could expect a roughly equal result... this need not entail giving the poor kid rich parents, but giving them enough other advantages to make up for the disadvantages of family background. But what Roemer and his co-author Julian Betts have shown is that such a policy could be enormously expensive. Based on what we know about the return to spending on education and other developmental policies, the bang for the buck is not that big, and the gap due to differences in family background is huge.

As Klein writes, Republicans often talk equal opportunity against Democrats' alleged support for equal outcomes (egalitarianism). But it's easy to imagine that any policy approaching true equality of opportunity would be much more costly to taxpayers than a highly redistributive tax-and-transfer egalitarianism. That would require the Republicans, based on their rhetoric, to be the big social spenders. Not really what they have in mind.