President Franklin Roosevelt quietly favored the left-wing Republican (or "Loyalist") government, but intense pressure by American Catholics forced him to maintain a policy of neutrality.

Americans had long recognized the importance of navigation rights on the Mississippi River, as it was the only realistic outlet for many settlers in the trans-Appalachian lands to ship their products to other markets, including the Eastern Seaboard of the United States.

Ambassador Luis de Onís who arrived in New York in 1809, representing Fernando VII's government, was refused an audience to present his credentials to President James Madison.

"[27] In the United States, Spain was viewed as permanently condemned by the Black Legend, and as a backward, crude, and despotic country that opposed the Monroe Doctrine and Manifest destiny.

Irving's official reports on the ensuing civil war and revolution expressed his romantic fascination with the regent as young Queen Isabella's knight protector, He wrote with an anti-republican, undiplomatic bias.

[31] In a letter to Hugh Nelson, U.S. Minister to Spain, Secretary of State John Quincy Adams described the likelihood of U.S. "annexation of Cuba" within half a century despite obstacles: "But there are laws of political as well as of physical gravitation; and if an apple severed by the tempest from its native tree cannot choose but fall to the ground, Cuba, forcibly disjoined from its own unnatural connection with Spain, and incapable of self support, can gravitate only towards the North American Union, which by the same law of nature cannot cast her off from its bosom.

[34] Another source of conflict and rivalry was the Captaincy General of Santo Domingo, recreated when Spain annexed the independent Dominican Republic at the request of President Pedro Santana in 1861.

[37] However, since neither the Union nor the Confederacy would sign a formal treaty guaranteeing that Cuba would never be threatened, Madrid remained convinced that American imperialism would resume as soon as the Civil War had ended.

At a time when women were not invited to public political conversations, Coronado succeeded in persuasively arguing against Spain's imperial legacy and urging support to rectify her nation's past colonial blunders, especially the introduction of slavery to the Americas.

[43] In June 1897, President William McKinley appointed Stewart L. Woodford to the post of Envoy Extraordinary and Minister Plenipotentiary to Spain, in a last attempt to convince the Spanish government to sell its colonies.

Many historians and journalists pointed out also the needless nature of this war, because up to that time, relations between Spain and the United States had always enjoyed very amiable conditions, with both countries resolving their differences with mutual agreements that benefited both sides, such as with the sale of Florida by terms of the Treaty of Amity.

A New York Times article dated June 3, 1921, called "How Spain Views U.S.", quotes a Spanish newspaper (El Sol) as declaring that the "United States is a young, formidable and healthy nation."

"The disgust and anatagonism it aroused in him", writes C. Brian Morris, "suffuse two lines which he expunged from his first draft of 'Oda a Walt Whitman': "Brooklyn filled with daggers / and Coney Island with phalli.

The Catholics insisted that lifting the embargo in favor of the Republican government "could only be the act of a hypocrite or a sucker" because, according to them, priests and nuns weren't given proper burials and were immolated by the anarchist elements of the Loyalist coalition.

The Soviet Union provided aid to the Loyalist government, and mobilized thousands of volunteers to fight, including several hundred Americans in the Abraham Lincoln Battalion.

Wallace Stevens, Langston Hughes, Edna St. Vincent Millay, Randall Jarrell, and Philip Levine also wrote poetic responses to the Spanish Civil War.

[62] Kenneth Porter's poetry speaks of America's "insulation by ocean and 2,000 miles of complacency", and describes the American "men from the wheatfields / Spain was a furious sun which drew them along paths of light.

As Secretary of State Dean Acheson increased his pressure on Truman, the president, stood alone in his administration as his own top appointees wanted to normalize relations.

The Spanish diplomacy, led by Fernando María Castiella, showed disregard for what Spain regarded as the unconditional US support to the State of Israel and for the American attempt to sow discord among the Arab nations.

[74] Between 1969 and 1977, the period comprising the mandates of Henry Kissinger as National Security advisor and as Secretary of State of the US during the Nixon and Ford administrations, the US foreign policy towards Spain was driven by the American need to guarantee access to the military bases on Spanish soil.

A month after the coup was suppressed Haig visited Madrid to mend relations with the King, Prime Minister Leopoldo Calvo-Sotelo, and Leader of the Opposition Felipe González to prevent it from interfering with Spain's entry into NATO.

[81] In regard of the military bases, the 1986 referendum on NATO membership and its result provided the Spanish government led by Felipe González with some leverage vis-à-vis the re-negotiation of the bilateral agreements with the US, and thus Spain asserted a larger degree of sovereignty.

Aznar actively encouraged and supported the Bush administration's foreign policy and the U.S. invasion of Iraq in 2003, and was one of the signatories of the letter of the eight defending it on the basis of secret intelligence allegedly containing evidence of the Iraqi government's nuclear proliferation.

During the electoral campaign Zapatero had promised to withdraw the troops if control in Iraq was not passed to the United Nations after June 30 (the ending date of the initial Spanish military agreement with the multinational coalition that had overthrown Saddam Hussein).

[89] The decision aroused international support worldwide, though the American Government claimed that the terrorists could perceive it as "a victory obtained due to 11 March 2004 Madrid train bombings".

[90] American officials were irked by the fact that Miguel Ángel Moratinos, Minister of Foreign Affairs, chose not to meet with Cuban dissidents during a visit to the United States in April 2007.

However, Morales’ plan to nationalize the gas sector of Bolivia caused tension with Spain, as Repsol, a Spanish company, has major interests in that South American country.

Summit in Prague the two held a 45-minute meeting, and afterwards shared a photo-op for the press, where Obama called Zapatero a friend, and said he thinks that the two nations would establish an even stronger relationship in the years to come.

Meanwhile, Borrell had a meeting with Secretary of State Mike Pompeo, where the Spanish delegation showed concern for the US protectionist drift and discrepancies between the two countries were found in regards to their approach to migration policies.

[104] On 28 June 2022, following a meeting of US president Joe Biden with Spanish prime minister Pedro Sánchez in La Moncloa, both leaders issued a joint declaration to enhance the relations between both countries (updating the 2001 previous joint declaration signed by Josep Piqué and Madeleine Albright), which included an agreement on increasing the number of US warships in Rota and on the importance of permanent cooperation between both countries in response to the challenges of irregular immigration in North Africa.