text:  The alleged shooter is dead. One other person in the crowd is dead, and two people were seriously injured. That's according to the Secret Service. Bill, we've been talking to you because you have done advanced security work at rallies like this for a long time. Again, those are all clear facts, but there are so many more clear facts to come, and we know that things can change. So let me ask this. What are the biggest things that you're wondering about, given your experience at events like this and given what happened? What would you love to know, given your expertise?