There are defensible arguments for proposition that President Obama has been more successful than he gets credit for on the left. (I don't tend to make them, because in my point of view, Obama had the potential to do much more.)
But Jon Chait chooses the most boneheaded example I can think of to attack demanding liberals: be happy, he tells us, with the cost containment in the Affordable Care Act:
[L]ists of liberal accomplishments tend to totally ignore health care cost containment.The Affordable Care Act was an attempt to do two things at once -- cover the uninsured, and tame runaway health care inflation. The latter goal was a crucial administration priority, but it never attracted much liberal passion in Congress
Obviously there is a strong argument that cost containment in Medicare is an important technocratic goal. But is it really a liberal one?
A few years ago I read someone else's thoughts on basically this point (I can no longer dig up a link). The underlying observation was that the liberals were in favor of healthcare reform because we wanted to give more people healthcare. If that meant that we got things we didn't care about along the way (like cost control), fine, but that was never the point. Heck, if you cast the cost controls in a slightly different way (as the Republicans did in 2010) you can plausibly call them cuts to Medicare. And it doesn't take a genius to figure out that NO LIBERAL SUPPORTS THAT CONCEPT.
Chait doesn't understand this for some reason.
As a person who will support the President next year because the alternative is sure to be worse, I really hope that the President can find better defenders.