“The Line Becomes a River” by Francisco Cantu is a border guard’s impressions on the hard realities of policing the frontier between the US and Mexico.  “South and West” by Joan Didion recounts her impressions from her travel notebooks  In trip through  Louisiana, Mississippi, and Alabama, she encounters a   preoccupation with race, class, and heritage. And in California notes, she finds a region focused on the future; a where  “shucking off roots is the one real tradition.”