Suppose someone is overheard in a restaurant saying that he wants to blow something up. And someone tells us about it. What should we do? Don't we need to find out if he was serious? Or was he drunk? The way to do that is to have someone engage him in an undercover way, not show up with a badge and say, 'What are your thoughts in regard to terrorism?’ Plenty of times it's a wing nut or some drunk, and we drop it.