Answer:
This sensational front-page headline about a $50,000 reward would likely get the attention of readers. This "reward" is metaphorical as they would give no such reward but the intention was to capture the interest of readers.
It also blames an unnamed enemy for an explosion and destruction of the warship Maine, without a note about an investigation about what caused the explosion.
The story of the explosion and destruction of the warship Maine may cause people of New York to become hostile to Spain as they were the most likely perpetrators of the act and may lead to calls of war of maltreatment of Spanish immigrants in the city.