Obama has a particular challenge.
He is in a hunkered marathon of damage control.
His signature achievement as president is in trouble, polls show Americans trust him less than they ever did, and he's at that stage in his presidency where his legacy is beginning to be defined.
Even the most pure-hearted pilgrim would have to lash himself to the mast to keep from engaging in spin to manage these problems.
But when you spin in the middle of a credibility crisis, the garden-variety shadings required by the office can make your problem worse.
That's bad for the president's standing and for his party, but it's also bad because it means everything the president says gets a downgrade.
If no one listens or believes you, it's hard to make the case for any good news.
http://www.slate.com/articles/news_and_politics/politics/2013/11/barack_obama_s_broken_health_care_promises_does_the_president_have_any_credibility.html?google_editors_picks=true