Final answer:
Post-Civil War Imperialism focused on expansion primarily in Asia, Africa, and Latin America, not in Australia, which was not a significant target for expansion by the United States or European powers after the Civil War.
Step-by-step explanation:
Post-Civil War Imperialism was a focus on expansion in several continents after the American Civil War, including Asia, Africa, and Latin America. However, it did not significantly include Australia. During this era, industrialized nations such as European countries and the United States sought to expand their territories and influence for economic and strategic reasons. Notably, the 'Scramble for Africa' led to European dominance over the continent, and spheres of influence were established in Asia. Although not a major imperial power like the European nations, the United States acquired territories such as the Philippines and exerted influence in Latin America through economic dominance. Hence, the correct answer to the question is D. Australia, as it was not a focus for Post-Civil War Imperialism by these nations.