I Think I Know What Happened at the Pentagon
Possibly some poorly visualizable holo-trick was also used in conjunction with the beam weapon to fool witnesses on the ground-- this may be not unlike what happened at the South tower.
Importantly, "flight 77", whatever it was, never came near the light poles. It wasn't even on the right trajectory.
Possibly, some "flight 77" over flew the Pentagon about the time of the attack to make more distant witnesses think a plane flew into the building.
*Interestingly, the same C-130 flew over both the Shanksville and Pentagon hits. It's rather tempting to wonder if this C-130 was packed with 757 fuselage pieces (in American and United colors) to sprinkle from above.