U.S. President Joe Biden officially blocked Nippon Steel's proposed $14.9-billion purchase of U.S. Steel Friday over national security issues, dealing a fatal blow to the contentious merger plan with the Japanese company. Nippon Steel and U.S. Steel blasted the decision, saying Biden cited no credible evidence to support the national security claim and vowed to sue. We speak with Scott Laing, a professor at the School of Management, University at Buffalo.