Many of the comments here question the necessity of dedicating a whole book on "soft power." I agree with this, Except that I think, this is not necessarily because soft power is a trivial issue -it most certainly is not.
Why then, so much discomfort expressed by so many readers? Firstly because, even if you are a really hard-boiled "realistissimo," the importance of soft power goes without mentioning. It is almost taken for granted, and Nye Jr, the IR genius as he is, commits one of the rather greater sins that readers find hard to tolerate: redundancy. He seemingly repeats and repeats his points to the degree that they almost lose their meaning. And no one has the patience, especially when there are so many books awaiting on the shelf to be read.
But a second why: Why then, Nye, one of the living legends of the IR literature, having all the access to the journals and reviews of the area, preferred writing this book, a tedious task one imagines, instead of an article on the topic? I think there are three main reasons to this: first he, rightfully, wants to take credit of the fact that he is the one who has coined the term "soft power," especially after the widespread acceptance the term has received. By writing a book that addresses more to the general public than to the more obscure academia, he claims his right on the word. The redundancy and dullness of the book seem to be an acceptable price for that. After all, not many, even amongst the professionals of the area, do not read, the forefathers of the discipline, say Morgenthau (They are more likely to read people who read and wrote about these forefathers.) Then again, Morgenthau and his likes are known to be among the founding fathers of realism, if not international relations as a disipline. Similarly, even though this book is not likely to become a veritable reference for most, it successfully guarantees that Nye will be remembered as the guy who invented the term. Secondly, despite its spreading use, Nye is aware of the fact that the term is being taken out of context, and most of the time employed wrongly, especially by politicians. So he tries to avoid misunderstandings as far as the meaning of the term is concerned. And thus, he is entitled more than anyone else to draw the clear line between what he intended the term would refer to and what people perceive it to mean. Third, his choice of style, that the book is reminiscent of a policy recommendation paper rather than an academic analysis is informative. What the author tries to do is to put out a manual. That is, the meaning of soft power once clarified, he proceeds to describe how to put it into use by policy-makers.
Power is one of the most important themes of international politics as a discipline. Almost all theories are identified, in some way or other, as to their approach to the issue of power. And for many scholars of the field, there are many aspects of power. For example, there is a general misconception, if not a sweeping assumption, with regards to realists: they are considered as dismissive of whatever they deem unrelated to power, and also picky as to the very definition of power itself, which means it is only "hard power" that interests them.
I tend to think that this is a false statement. Not only because there are no realists out there who are possessed by the pure credo, or the "idéotype." Surely they are aware and appreciative of the value of other factors and other aspects of power. The realist can be, in that sense, likened to the physicist, who, by fear of not being able to reflect all the physical variables in his computations, take some and leave some. The decision of what to take and what to leave might indeed prove fateful in the end. But most of the times, it is more practical to eliminate the noise by leaving out certain factors, than overestimating their importance. It is the amount of noise that forces theorists to make the decision.
I am not sure, however, that "soft power" can be disregarded even by the purest realist without risking to challenge the premises she has set out on in the first place. Because the definition of power made by Nye in this book is compelling and conforms almost mot-à-mot with its conventional definition by the realist clique (power means the ability to get the outcomes one wants.) Thereby, it is not so much academics as politicians he is addressing; especially the Bush Jr administration, who got it all wrong in everything they attempted. Hence the polite chiding, veiled condescension in the author's tone.
Well, thinking back now, apart from, and in addition to, an attempt by the author at patenting the term he invented, the book might be perceived also as a position paper by a prominent and responsible academic, an invitation to a saner, respectable foreign policy; an apology for the evaluation of next generations, that he didn't remain inert while all the craziness was unfolding, that he did take a side.
(And there are some useful lessons in the book for those foreign policy makers who are under the delusion that soap operas are great sources of soft power. Well guess what, they are not!)