Final answer:
The debate involving German nationalism and the Sectional Crisis in the U.S. dealt with how a nation-state should be formed based on language and ethnicity, and how the issue of slavery revealed deep sectional divides between the North and South, leading to the Civil War.
Step-by-step explanation:
The debate on the form of German nationalism during the 19th century and the Sectional Crisis in the United States revolved around the concepts of nationalism and sectionalism. Nationalism fueled a desire among Germans to form a nation-state that represented the identity and aspirations of German-speaking peoples, posing a question of whether to include or exclude Austria and its diverse ethnicities. This debate eventually concluded with the idea that states could join Germany if they left behind their non-German territories. In contrast, American nationalism during the early republic was challenged by sectional differences exacerbated by disagreements over the expansion of slavery, which revealed deep divisions between the North and South. The Missouri Compromise was a significant milestone in this debate, with the Tallmadge Amendment highlighting the sectional rift that aligns more with geographical lines rather than party affiliations. The disagreements between the North and South over economic interests and political power related to slavery foreshadowed the coming Civil War.