That quotation alone is worth the price of the book! The kingdom of God is just that, the kingdom of God. Trying to mix our best efforts at creating a kingdom just isn't going to work. God's calling is higher and beyond our meagre efforts.
Jesus said you can't serve two masters. I fear some have sold the true master for a chance to influence the current world. At what cost?
Lord, have mercy! Open our eyes that we may see! That we may catch a vision of your kingdom!