Dr. Giles does spend time debunking the libertarian myth. Read the book.

My take on libertarianism is that Karl Marx was right. If capitialism is given free rein, it will creat a small class of uber-rich and a mass of poverty. We can justify that the uber-rich worked hard, worked smart, and developed their talents, so they deserve the wealth they earned. But such a society is likely to generate political movements that will topple the social order. When that order is gone, it will be hard for the uber-rich to create more wealth and enjoy it.

So libertarianism may be "right," but it is untenable.