What would you have done if you were the Park Service, Secret Service or whomever?
Shot at him with a Stinger, sending flaming debris raining down on tourist walking the sidewalks?
Arrest him two years ago on suspicion of "grumbling and distrust of the Federal government"? ("You Freepers, line up to the right and await your turn for handcuffs!")
Complete defense of a large, open access area is almost impossible.
What would a boss pilot do?
Somehow I suspect that if his cause would have been something other than campaign finance reform....say, Pro Life, or Gun Rights....he would have met that Stinger missle.
... What would you have done if you were the Park Service, Secret Service or whomever? ...
I am not a weapons expert but the Capital and White House must be impenetrable regardless of collateral damage. Whatever it takes, shoot it down and ask questions later.