Chemical weapon poses the most significant threat

Based on what you have learned through the course material and outside academic sources, assess what particular chemical weapon poses the most significant threat to the United States; analyze the means by which state or non-state actors could make or acquire this specific chemical weapon; and hypothesize the physiological, psychological and social impact of an attack using this weapon. Consider both recent uses of chemical weapons in Syria and the United Kingdom and how either of these methods of attack might be used in the United States.