Friendly-fire does not go on for multiple waves of cordinated sea and aerial strikes. Those are the hall-mark of a planned attack.
Or they could be an ad hoc attack on a misidentified target. The fact that multiple waves were involved supports this - you don’t need all that to sink an unarmed ship; all you need is one well-placed torpedo.
Nope - she was fired upon by two torpedoes, one of which blew a fifty-foot hole in her. This, 20 minutes after having been positively identified by multiple Israeli aircraft whom had attacked her. Voice recordings of the pilot’s radio communications identifying the Liberty are preserved.
Why would they attack Egyptian ships with anti-infantry weapons instead of anti-ship missiles?
Given that this is GQ, could we have some cites for that? According to the wiki article (and the NSA itself), the only recordings are from helicopter pilots after the attacks took place, at which time they were still referring to the ship as Egyptian. The NSA does NOT have any recordings of pilots definitively identifying the Liberty.
The wikipedia article (which seems unbiased and detailed) indicates that the planes broke off their attack after seeing non-arabic lettering on the hull off the Liberty, but did not “positively” identify the vessel. The torpedoing took place in what can only be described as the fog of war – signals were misinterpreted and the Liberty fired on the torpedo boats with machine guns (one exploded) after a command to cease fire was not communicated.