In war -- bad things happen. the USS Liberty was a "neutral" warship in the middle of a war zone and there in that war zone without the cautions due. The Navy and teh NSA had absolutely foolishly sent it there alone and unannounced.
The pilot was right -- the mistake wasn't his. His mistake would have been in NOT attacking a unknown warship in a war zone.
Clue 1, announcing the arrival and departure of intelligence gathering ships and aircraft would have a rather serious impact on their effectiveness. Clue 2, intelligence gathering ships and aircraft are clearly marked.
You call people names instead of addressing the message. There are several old saying that go along with that... I know, you couldn't help yourself...