I've been a Heinlein fan for just about as long as I've been an SF fan (somewhere around thirty-five years). But when I read this collection some twenty-odd years ago, it nearly turned me off to the old man altogether.
The fiction is pretty good (although even that isn't Heinlein's best). But to describe the nonfiction accurately, I'd have to use words that Amazon will remove from the review anyway.
For the most part, the pieces collected here represent a side of Heinlein I strongly dislike. Though I respect _Starship Troopers_, it's never going to be my favorite Heinlein novel no matter how many times we quibble over the precise definition of "fascism" -- and I'm not going to have much respect for the nonfiction in this collection.
Heinlein (who bought into the Korzybski/General Semantics fad pretty early on) spent a lot of years dismissing philosophers as tailchasers who derive their premises from their conclusions. But his own attempt at philosophy, as represented here in e.g. "The Pragmatics of Patriotism", is very nearly the worst writing on ethical philosophy I've ever seen.
Then, too, people who knew Heinlein report that despite his overall gentlemanly demeanor, he could be pretty churlish toward people who disagreed with him. Well, he's certainly unpleasant here; anybody who doesn't agree with him on the need for massive nuclear buildup is dismissed as a poltroon or a custard-head. Even in the unlikely event that I thought he were _right_, I wouldn't find this a very helpful approach.
Perhaps more surprisingly, his popular writings on _science_ aren't very good. Asimov's reputation as the "great explainer" is in no danger here.
This volume is second only to _Grumbles from the Grave_ in cementing Heinlein's posthumous reputation as a rather mean-spirited fellow whose fictional characters were generally much better company than he was. When I want Heinleinian company, I'll stick to D.B. Davis, Manuel Garcia O'Kelly Davis, and (maybe) Lazarus Long.
And when I want to read some humane nonfiction by an SF master, I'll still turn to Asimov. I credit Heinlein with three magisterial novels, several imperfect-but-great ones, and a good number of brilliant short stories. But the stuff in this book should have stayed in his drawer.