Final answer:
One reason NOT why many in the American public wanted to declare war on Spain was the fear of Spain invading Washington DC.
Step-by-step explanation:
The reason why many in the American public wanted to declare war on Spain can be attributed to a few factors, but one of them was NOT the fear that Spain would invade Washington DC. This fear was not a prevailing concern among the American public during the time leading up to the Spanish-American War. The other three options mentioned in the question were indeed reasons why many wanted to go to war with Spain. The potential for losses to American investments in Cuba, the sinking of the USS Maine, and the DeLome Letter were all significant factors that pushed the American public towards supporting war with Spain.
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