It's "the menacing social and political contexts. There are absorbing characters and erotic regeneration, but Roth’s greatest novels typically depict Americans brought down by the forces of the country’s hypocrisy. This time, Roth keeps everything in plain sight, reducing much of the fear of the unknown, leaving little for the reader to ponder."
How true. I should have thought of that.
I have noticed Roth submitting himself to being interviewed by Tina Brown on The Daily Beast and his publisher taking out a full-page ad in The Times for this book, which together make me wonder if the book is not doing so well.