The author's focus is almost entirely on economics.
He's an economist. I heard him say in an interview on NPR's Fresh Air that he prefers to speak only to the economic angle rather than other more political issues because he prefers to talk about something he knows.
Note, conservatives: His hero is Ronald Reagan. Ronald Reagan is not my hero. Yet on this we agree: Both Reagan and (he ruefully admitted) Clinton were better stewards of the public's interest than George W. Bush.