Being the first time of me hearing about this happening in the past, I can wonder at the excuses used to pacify US opinion back then.
"Shalom sorry we didn't see you clearly, we assumed the flag was a deception by our enemies as we detected its ELINT emmissions and scanning systems - we naturally thought it was another countries boat..."
springs to mind, or
"...Opps, we got the wrong boat/intel..."
or behind closed doors...
"...oh you were only evesdropping on the them and not us as well, please forgive/forget this 'little' hiccup, and keep giving us 'gifts' and if possible, the intel from before we sank it..."