Why hasn't Britain recovered more quickly?

Ryan Avent has an excellent post, channeling an Adam Posen report (pdf).  Here is one summary bit:

Financial issues, euro crisis, austerity and oil can account for a lot. It seems possible that structural factors are more of an issue in Britain than in America.

It's worth noting that the main "austerity" culprit here seems to be the increase in the VAT, not the spending cuts (proposed or real) per se.