Let review this farce.
You are a supposed highly trained, high paid security professional working for the state of the class US Secret Service. SOP is to lock down any roofs with ladder access within sniper range of a high risk target. You are assigned to guard the highest risk target in the world right now.
However, magically, yesterday you total forgot to secure a roof top 150 yards from the opposition party’s political candidate. A roof top that also had line of site to the egress path the candidate would be rushed down in case of an emergency.
Magically this “random nut” penetrated your security zone, wile carrying a rifle, decided to crawl up onto that roof and get off 8 shots at said high value target before you even responded.
If random people out here can see the obvious flaws in the security set up, why did the highly paid, highly trained people running the SS miss all of them?
That's why I don't blame the sniper for not shooting first. It was probably just as incomprehensible to him as it is to us that anyone could be positioned on that roof who wasn't part of the security team.
3 shots by the perp. Vid closer to the building he was on definitely has the next 5 with a much different power (louder), acoustic signature (including echo), and rate.
As for your last question, it appears the Biden Admin’s woke incompetence has soaked into the SS. Lack of enough agents likely didn’t help, but that still doesn’t explain no local LEO’s on the roof. It’s not like there were not plenty of local agencies / dept’s to draw from. I’ll bet there are 100 within a 50 mile radius.