If you believe in checks & balances, separation of power, and government restraint, this can be a depressing book to read. This was originally published during the twilight of the George W Bush administration, with a preface dated right before the assassination attempt on Donald Trump.
Throughout all of it, Healy does a good job outlining the American presidency's path from chief magistrate to "extraconstitutional monstrosity." In short, presidents exceed the bounds of their power, the courts are extremely deferential when legal challenges arise, Congress cedes its authority to the executive branch, while voters, historians, and pop culture often lend their applause to this outcome (especially when their side sits in the White House).
A sober reading of this should give one pause when they hear how democracy in America is at stake in our elections. Democracy's ascent in America has coincided with the ascent of the imperial presidency: wars without authorization, constitutional restraints tossed aside, statutes violated, power usurped from other branches of government. Is this what Progressive reformers had in mind when they saw the president as our "national representative"? Is there a meaningful distinction between this and conservative "unitary executive theory"?
Healy's book covers a lot of the same terrain as Andrew Napolitano does in his book Suicide Pact. A reader probably doesn't need to read both books to get the main idea. Healy's book feels a little more focused, although he doesn't cover "enhanced interrogations" beyond addressing the "Torture Memos." Napolitano's strength is his discussion of natural rights. Either book is recommended.