Alan Cassels 
Ideology and International Relations in the Modern World [PDF ebook] 

Cassels offers a novel perspective on the part played by ideology in international relations over the past two centuries. His treatment is not restricted to the familiar totalitarian ideologies of communism and nazism, but also includes conservatism, liberalism and nationalism. The focus and emphasis given to ideology in an historical survey of such broad scope make this book unusual, and even controversial.