J. Gresham Machen saw in 1933 what many are trying to say today about the need for private education.

The only way in which a state-controlled school can be kept even relatively healthy is through the absolutely free possibility of competition by private schools and church schools; if it once becomes monopolistic, it is the most effective engine of tyranny and intellectual stagnation that has yet been devised. (J. Gresham Machen: Selected Shorter Writings, 167)