Yes, it's indeed a good thing they were able to determine the foam was the reason for the loss of Columbia.
I wonder if they could have spotted the foam before it hit the wing during a night launch. Perhaps once it passed an angle where the flames from the SRBs would have lighted it up.
After testing come the operational flights. Many Soyuz launches take place when the rocket is invisible (night launch or fog) and most of Ariane launches take place at night.
Being able to see a Shuttle flight very clearly all the way until booster separation, has occured but not all the time.
I wonder if radar could replace optical instruments to "visualize" every launch.
But then, the foam issue would not be relevant if the next generation spaceships are launched on top of the rocket instead of strapped along it.

Raoul