Granted that it was the christening of the Enterprise B but who was the idiot that allowed this ship to leave spacedock. No ship doctor and no photon torpedoes and how did Harriman become Captain and Kirk's successor?
It wouldn't be the first time in history that an official launch/unveiling/opening of something was kept on schedule before the thing was actually ready. Take any video game for instance. How many glitches do most games have that could have been fixed if they just waited.
Because the movie needed a reason to make Kirk and Co. look good. The character of Captain Harriman is a theatrical device known as a "foil," as was the rest of the Enterprise B crew.
What I don't understand is why the Enterprise B is the "only ship in range" when it's still in the Solar System, which is the capital the Federation. Surely there should be a half dozen capable starships still hanging around space dock.