President Pierce could count on his party for support in any plan he chose to pursue to take possession of Cuba. The Democrats were dominated by Southern slave owners and they lusted for the annexation of the island to become another slave state. Furthermore, it would not only increase the value of their slaves, but also equalize their competitive position to Cuba in the sugar markets.
Other journalist stoked the flames of passion for annexation by reporting that the Spaniards were once again flirting with a free labor system in Cuba. Spain had seen the writing on the wall and were again courting British assistance in maintaining their hold on the island. The British, of course, were looking to use Spain's dilemma as an excuse to press for an end to slavery in Cuba.
In a cursory examination of the diplomatic messages to Europe of that time, it appears that Pierce was following the lead of his predecessors. He sent notes to the major powers in Europe reaffirming the American policy of honoring Spain's authority over Cuba, and that no move to transfer that authority to another nation would be tolerated. However, the men he chose to deliver those messages were all decidedly and publicly committed to revolution and annexation. Indeed, a couple had records of antagonizing the governments they were sent to. Now there's a mixed signal if ever there was one.
President Pierce's diplomats in Europe began conspiring to use the uncertainty they were creating to make another attempt to purchase Cuba. They convinced Spain that neither England nor France had the capability or the will to intercede. This, they hoped, would lower the purchase price.
Before the Secretary of State could dispatch the authorization to make a formal proposal to purchase the island, Cuban port officials in Havana seized an American merchant ship, the Black Warrior. A diplomatic incident ensued, and plans to purchase Cuba were shoved to the back burner.