Nugent concludes his survey with words:
Chapters are as follows:
Texas, 1811-1845: Overpopulating and Conquering
California and New Mexico, 1846-1848: Southward Aggression II
Populating the Empire
To Alaska and Across the Pacific
Around The Caribbean
Nugents conclusions are not new ones. What Nugent does do is to put these various movements and periods together, and concentrating on the imperial tendancies we can see that his conclusion is the only one that matches with the reality of history. All through the book he brings to life the thinking of the leaders and exceptionalism and the notions that only white Americans can make best use of the territories as they present themselves on the horizon.
The postscript accurately describes our imperial appetite as a changed form that does not include direct possession. We have many bases around the world and those forces are there to make sure we have access to raw materials and markets.
These are hard lessons to learn but stopping our ears and eyes do not make them go away. Being aware of our past might help change our views and make our place in the world better. By being aware of our past dark side we may someday really stand for those ideas of liberty.