Either it was a terrorist missile, or it was our own US Navy, on training in the area that fateful night.
Other variations are possible. Perhaps there was a terrorist plane loaded with explosives trying to take out flight TWA 800, and the Navy was on high alert, tracking this, and tried to shoot down the terrorist, but was a few seconds late, and the missile(s), the terrorist and TWA 800 basically all end up in the same general area, putting on a real fireworks show.
We are in mooootual agreement.