Re: Temporal Cold War and the rest of Trek history
So how come Picard and co act like Starfleet has never encountered anything like the Borg in "Q Who?" ?
Because Starfleet officers don't know everything anymore than anyone else knows everything about their profession. The material pertaining to the Borg may have been classified and unavailable for Picard to access. It's possible he became aware of what happened at a later time, but wasn't aware when the events of "Q Who?" took place.
"Many things seem clever to an imbecile." --Captain Thelin th'Valrass, USS Enterprise-- "The Chimes at Midnight"