Explain the connection between jingoism and mckinley's foreign policy

McKinley hoped to make American producers supreme in world markets, and so his administration had a push for those foreign markets, which included the annexation of Hawaii and interests in China. While serving as a Congressman, McKinley had been an advocate for the annexation of Hawaii because he wanted to Americanize it and establish a naval base, but he was unable to get the two-thirds vote. One notable observer of the time, Henry Adams, declared that the nation at this time was ruled by "McKinleyism", a "system of combinations, consolidations, and trusts realized at home and abroad." Many of his diplomatic appointments went to political friends such as former Carnegie Steel president John George Alexander Leishman (minister to Switzerland and Turkey). 

During this time there were some overseas conflicts, mainly with Spain. The U.S. had interests in Cuba, the Philippines, Hawaii and China. McKinley did not want to fully annex Cuba, just control it. In the Philippines, he wanted a base there to deal with China that would give the U.S. a voice in Asian affairs. Stories began to emerge of horrible atrocities committed in Cuba and of Spain's use of concentration camps and brutal military force to quash the Cubans' rebellion. Spain began to show it was no longer in control as rebellions within the rebellion broke out. The Spanish repeatedly promised new reforms, then repeatedly postponed them. American public opinion against Spain became heated, and created a demand for war coming mostly from Democrats and the sensationalist yellow journalism of William Randolph Hearst's newspapers. McKinley and the business community opposed the growing public demand for war, aided by House Speaker Reed. 

As a matter of protection for U.S. interests around Havana, a new warship, the U.S.S. Maine, was dispatched to Havana harbor. On February 15, 1898, it mysteriously exploded and sank, causing the deaths of 260 men. (In 1950, the Navy ruled that "the Maine had been sunk by a faulty boiler" and not by attack as was assumed at the time).[5] Public opinion heated up and a greater demand for war ensued. McKinley turned the matter over to Congress, which voted for war, and gave Spain an ultimatum for an armistice and a permanent peace. Although the Army was poorly prepared, militia and national guard units rushed to the colors, most notably Theodore Roosevelt and his "Rough Riders." The naval war in Cuba and the Philippines was a success, the easiest and most profitable war in U.S. history, and after 113 days, Spain agreed to peace terms at the Treaty of Paris in July. Secretary of state John Hay called it a "splendid little war." The United States gained ownership of Guam, the Philippines, and Puerto Rico, and temporary control over Cuba. McKinley had said, "we need Hawaii just as much as we did California", and Hawaii was annexed (see above). McKinley had begun by wanting only a naval base in the Philippines at Manila; in the end, he decided to take all of the Philippines, a move that led to the Philippine-American War. 

Throughout these ordeals, McKinley controlled American policy and news with an "iron hand". McKinley was the first president to have the use of telephones and telegraphs giving him access to battlefield commanders and reporters in mere minutes, and he used this to his full advantage. These ordeals also gave life to an Anti-Imperialist League movement at home.