This book, at only 350 pages, attempts to cover 4 centuries of Canadian military history; detail is necessarily sacrificed as a result. This is not necessarily a problem, if you're looking for an overview or introduction to the highlights of the topic. This book is very good at supplying this overview.
Having said that, the average armchair historian may find the lack of detail frustrating, especially in areas where lots has already been written, e.g., the War of 1812 and both World Wars. This is balanced by an overarching view of the whole of Canadian history, linking themes and observing the evolution over the course of several hundred years. For me, the interwar years were the most interesting because I've focused on detailed histories of particular events in my past readings. The post-WWII chapters are especially interesting and informative, and contain the most insightful analyses in the book. There are several pages of good pictures. It's always nice to put a face to the people involved. However, the maps are generally not detailed enough to be useful, mostly overviews of the general lines of advance of the army, for instance.
But ultimately, I can only award three stars. The title of the book is a bit misleading - perhaps it should be "A History of the Military of Canada" instead. Much more coverage is given to military organisation, conscription debates, etc. than are given to actual operations. I feel there should have been a better balance between these two broad areas. Even as an overview book, it could have stood to be 50-100 pages longer to flesh out the operational side.
In summary, this is a very good book if you are looking for an overview of the subject. It lacks detail, as expected for its length, but this is compensated for by drawing together themes from widely separated events. The major drawback is its emphasis on the organisational side to the expense of the operational.