In my opinion, the video is very clear. Nearby sodium lighting experienced a surge of power at nearly the same time as the Guidestones exploded into pieces, indicating a powerful electric field in the area.
There was no orange flash indicating high explosives and no saboteurs were caught on camera.
A lightning strike can be ruled out because there was none in the area at the time of the strike. Even if it was lightning, the time of the strike, 4:03.33, is a message only capable of being delivered by a DEW, which travel at 186,000 miles per second.
If it is known that this was a DEW strike, that would mean the US Military is responsible. They are the only ones with the available technology and control of Theater.
I had strong suspicions about the strike on the George Floyd mural for similar reasons.
I believe the fruits of POTUS45's formation of Space Force are now being realized.
Just posting my original thought. The brightness of the explosive flash made the camera briefly adjust its exposure level, leading to the light appear to flicker. It would be interesting to see the footage before the blast to see if anyone was visible planting an explosive.