Originally, the sinking of the ship, the USS Maine, was led to believe that Spain had blown it up while it was in the harbor near Cuba. Yellow Journalism was a practice where newspapers were encouraging people to sympathize or support the cause for the war against Spain.
But the reality was that there was a malfunction in the ship's engine that actually blew up itself. This was investigated years after 1898 when it exploded.
The ship's explosion itself caused people to want the United States to declare war against Spain because it killed Americans on board. However, because of the false information, Spain did not actually blow up the ship. The United States used the ship's explosion as leverage to declare war against Spain, in which they ended up winning the Spanish-American War in 1898.
