Final answer:
Americans were primarily motivated by patriotic sentiment to contribute funds to the war effort through the purchase of Liberty Bonds, which were promoted as a support to the troops and a national duty.
Step-by-step explanation:
The question asks about what motivated Americans to contribute the necessary funds for the war effort. The answer lies in the patriotic sentiment that was prevalent during the times of war. This sentiment was heavily utilized by the American government to encourage citizens to buy Liberty Bonds, ensuring they "do their part" in the war effort. The Liberty Loan Act was pivotal for the U.S. government to raise funds, collecting a substantial amount through the sales of these bonds, promoted with appeals to patriotism. Furthermore, during the Revolutionary War, the concept of patriotism was also important, as it inspired settlers to sacrifice for the general welfare, and was crucial in the formation of a political framework.