Final answer:
The U.S. founders focused on Montesquieu's and Rousseau's ideas due to their influential concepts. Montesquieu's separation of powers theory and Rousseau's social contract theory greatly influenced the structure and principles of the U.S. Constitution.
Step-by-step explanation:
The U.S. founders were motivated to focus on Montesquieu's and Rousseau's ideas as the basis for their new governmental foundations due to the influential concepts put forth by these philosophers. Montesquieu's separation of powers theory, which advocated for the division of government into separate branches, greatly influenced the structure of the U.S. Constitution. Rousseau's social contract theory also impacted the U.S. founders, as it emphasized the idea that governments should be based on the consent of the governed.
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