Was in a no fly zone. Came onto the grounds of the white house. How do you know what's necessary and what isn't? You don't.
we don't. but the men armed with rocket launchers and sniper rifles are trained to make a decision, and safety isn't the only factor. Imagine it was a drugged teenage girl, tied to a remote control helicopter and launched. If they can bring it down without hitting her with an RPG, it's desirable, right?
Since they don't know the situation, if they can halt the progress without destroying it (and any evidence), they should, and DID.
If he had come close to buildings, they would have probably dropped him. But it looks like he jsut went far enough to get himself on news and arrested, on purpose. In the USA, when avoidable, we don't execute people. Nicer to find out why they're there. if ISIS decides to drug college kids and launch them into the capitol using remote control choppers, it's nice if we can bring them down without killing, ye know?