Was the Constellation program a good response to the Columbia Disaster?

This is the next of my most recent series on space.  I posed the above question in
a previous post.

I think the answer is no.  Constellation is too ambitious.  The mission will require 10
launches to set up for the mission to Mars. It will take 2 years to complete the mission.
The odds of everything going to plan during all this time and over all these launches-
is not good.  It is also bad because they are throwing away the shuttle system
in favor of a new launch system.  This launch system needs its own shake down time.
Before it can be ready, many years will have passed.  In the meantime, nothing gets
accomplished.  Lastly, they are not showing the way to the future.  This doesn't answer
 the economic needs of the country.  It looks more and more like a luxury instead of a
necessity.  People may decide that they don't need the space program anymore.  That
would be a mistake.