Despite what most people think, there's a marked difference between funny and controversial. Here's the thing: Anyone can be controversial. Anyone. Octomom was controversial, George Bush was controversial, Tila Tequila was controversial. Fact of the matter is, you don't need even an iota of intelligence to get people to talk about you; Hell, the fewer brain cells you have, the easier it probably is.
Being funny, on the other hand, requires an amount of brain function that, quite frankly, the controversial are simply incapable of. Take Rush Limbaugh for instance: He may wobble about in his chair mocking Michael J. Fox's Parkinson's, he may wiggle his jowls to crack jokes about ethnicity and gender and sexual orientation, and he may take periodic breaks between self-medicating and having myocardial infarctions to go on the record saying he hopes our president fails, but he will never be funny. Why? Because he's simply not smart enough to be funny.
Such is the underlying issue with Denis Leary's "Why We Suck": It's hysterically funny, and I highly recommend it, but for all it's grand-standing, it's machismo and it's desperate attempts to puff out its chest in a display of masculinity, it's just not as controversial as it thinks it is.
Not that he doesn't try. He gives his chapters titles like "Matt Dillon Is A Giant Fag" or "Autism Shmaustism", but never lives up to his own lofty expectations. What he's saying is either already true, and widely known by all but those with no sense of reality, or it's just too generalized to his own life for it to apply on a larger scale. Let's face it: despite what you might believe, women are generally just as awful as men, and men as generally just as awful as women.
Actually, this would probably be almost irritating if it wasn't for the fact that this book is just flat-out fucking funny. It is balls to the wall, all or nothing, fuck you and all you stand for funny. In a way, it's sort of the literary equivalent of watching Supersize Me; yes, we all know that eating McDonald's is bad for you and that it will make you fat, but we watch it anyway because it's entertaining as hell. That's what it is: It's a collection of well-known or stretched-out truths, but retold in a way that at least makes them fun to relive again.