I don’t think the attack on education was a long-term manipulation thing. Rather, it evolved from the question, “Why are all these educated people turning into liberals?!”
That question demands an answer. They can hardly let the appearance that they’re dumb stand! So guys like Limbaugh started attacking “ivory tower liberals”. That resonated, they rolled with it. Then the Christians saw the opportunity, got their filthy fingers into the cracks, started undermining public education in favor of their own.