The expanding v-shaped exhaust trail is missing and the path is almost too straight and too vertical in my opinion compared to actual submarine launch videos. It is possible the helicopter searchlight story holds water. I think Q was referencing something else.
The trajectory makes this look more like a THAAD launch. Perhaps this is the missile that intercepted the threat launched elsewhere. There should be plenty of place to park a THAAD launcher along that sight line, and it stands to reason we would have them in the vicinity of Bangor. Just a theory. All the pics and long-exposure shots of missile launches I have found are curved trajectories, except THAAD.
The streak does not necessarily originate from the water. It could have been fired from the landmass in the background