According to the documentary, which featured interviews with several participants and examination of documents released many years later, the A4s did take off in a state of readiness which was described by a euphemistic term well known to naval personnel at the time as indicating that they were carrying nuclear armament. After calls to McNamara and Johnson they were recalled. Further aircraft were subsequently launched with conventional armaments in readiness to fly missions to protect the Liberty but they too were recalled. It was some hours before unarmed rescue missions were flown after the Israelis had withdrawn.

The film didn't make any wild allegations. The inference which could reasonably be drawn was that there were some contingency plans for an "incident" involving the Liberty (which had sealed orders covering these plans that remained unopened), but that the attack by the Israelis went beyond what had been planned and was probably carried out without the connivance of the US in its actual implementation.

I'm not trying to turn the Cat into a substitute site for conducting the argument about the Liberty (there are quite a few of them). I just wondered how well-known the incident was, given that I'd never heard of it before, and wanted to draw attention to what seem like sufficiently serious allegations as a reminder of the lengths that governments will go to to claim that "He started it", and take advantage of the chain of "retaliation" to broaden wars in directions which suit their longer-term strategies.

Parallels with the present situation are rather obvious.