Sowell writes this in his new book The Housing Boom and Bust. He is addressing how the government's affordable housing crusade played a major role in making the economy tank. Whether he knows it or not, Sowell is also addressing every human heart in matters far beyond economics.
Oh how easy it is for us to do great damage to the Church, our families and other relationships all because we have convinced ourselves that we are taking a stand for what's right. We need God's grace to protect us from cold, heartless self-righteousness as we live in accordance to His word. Don't just pray for the Spirit to help you to do the right thing. Ask Him to help you to do the right thing with the right heart and the right motives.