Final answer:
The Supreme Court rulings in McCulloch v. Maryland and Gibbons v. Ogden exemplified the nationalist era by strengthening federal authority and supporting national economic development. These decisions underlined the predominance of national legislation and federal powers, which were in harmony with the surge of nationalism during the Era of Good Feelings.
Step-by-step explanation:
The Supreme Court decisions in McCulloch v. Maryland and Gibbons v. Ogden significantly reflected the nationalist sentiments of their time by strengthening the federal government's powers over the states. In McCulloch v. Maryland (1819), the court ruled that the federal government had the implied power to create a national bank, and that states could not tax federal institutions. This decision underscored the supremacy of national laws over conflicting state laws, aligning with nationalist views that favored a strong central government. In the subsequent Gibbons v. Ogden (1824), the court extended the reach of the federal government by interpreting the commerce clause of the constitution broadly, giving Congress the power to regulate interstate commerce, including navigation, thus again reinforcing national authority.
Both rulings supported the idea of a broad interpretation of federal powers in matters of economic development, reflecting nationalism by implying a strong, unified nation was preferable for economic progress. The decisions played a pivotal role in shaping the balance of power between state and national governments, which resulted in the dominance of national interests—a keynote of the Era of Good Feelings. Additionally, they favored the creation of a stable economic system and infrastructure that would arguably benefit the nation as a whole.