Book excerpt: Instead of adopting the Precautionary Principle, Professor Sunstein argues for three steps: a narrow Anti-Catastrophe Principle, designed for the most serious risks; close attention to costs and benefits; and an approach called 'libertarian paternalism,' designed to respect freedom of choice while also moving people in directions that will make their lives go better. He also shows how free societies can protect liberty amidst fears about terrorism and national security."--BOOK JACKET.