Just off the top of my head the blunders in early 2010 were:
-scrambling after all the controversy to come up with a new goal, which led to Obama going to KSC and saying "It's asteroids."
By that time, Obama had acceded to congressional demands for Orion a Shuttle-derived launch vehicle. Given that, what else could he have done? Promising to go to back to the moon would have raised the question of funding for the lunar lander, which, as we've seen in the years since, Congress itself is unwilling to fund.
Though widely panned (and I'm one of the panners, and as you've pointed out it's not obvious that even the administration was serious about it), ARM seems a pretty clever way to satisfy the conflicting demands imposed by Congress (use Orion/SLS but don't give NASA more money), because the additional technology and hardware required was robotic and, therefore, much cheaper than a lander or a deep-space hab (and, incidentally, in line with the administration's desire to develop new technology).
In an ironic twisf of fate, it now looks as though ARM's large electric-propulsion system may survive ARM's demise. So some useful technology may come out of the whole sorry episode after all!