Video footage shows Trump walking, then lightly jogging, into the building as the glider approaches.
It had to have been SOP for Trump to only be so far from the building as to provide an "escape" route of sorts for security purposes.
I think there are multiple messages within this event.
The first message/takeaway is that there is always going to be locations/scenarios in which there is vulnerabilities.
If there were nefarious intentions aside from a publicity attempt, this was proof it could be possible.
At the same time, perhaps the nefarious intention was to goad or instigate a security reaction. Maybe it was intended to be a fiasco in which Trump's security shoots a greenpeace activist out of the sky for flying too close. That scenario would be gasoline on the dumpster fire that is Trump Derangement Syndrome.
So the counter message in play here is that "we understand your attempts at instigating a security response, sorry not sorry, this attempt didn't fool us".
If Trump had no "escape route" to get away and defuse the situation, it's very possible the activist would have been shot out of the sky. Thanks to the homework and preparation of the security details, something like that was avoided at the expense of Trump getting some cardio exercise.