As a previous Uncle Sam Pirate, I can tell you, there are many factors that would have come into play. Currents play havoc with ships under normal power, let alone a ship experiencing power issues. In an attempt to slow forward progress they would most likely have gone full a stern. At that point the rudder becomes your enemy as far as trying to control directional stability. My guess is that that ship was not equipped with directional screws or even thrusters. So, the rudder would be in the wrong position for an emergency full a stern situation. The shaft/s would also take time to change direction, when in open seas, this causes erratic movements, but there normally is nothing to hit. Couple that with intermittent power failures and all kinds of hell breaks out.
We almost hit the bridge at Astoria on our way to Portland once, and that was going up stream at the transition to low tide. All that water moving around has way more power than you can possibly imagine. This to me doesn't look to me as an intentional act, but the power issues could have been.
