Background , early Atlanticist leader Prior to the World Wars,
Western European countries were generally preoccupied with continental concerns and creating
colonial empires in Africa and Asia, and not relations with North America. Likewise, the United States had little interest in European affairs and was busy with domestic issues and interventions in Latin America and Canada, despite gaining self-governing
dominion status through the
Canadian Confederation in 1867, had yet to exercise full foreign policy independence as a part of the
British Empire. Following
World War I, New York lawyer
Paul D. Cravath was a noted leader in establishing Atlanticism in the United States. Cravath had become devoted to international affairs during the war, and was later a co-founder and director of the
Council on Foreign Relations. In the aftermath of World War I, while the
US Senate was discussing whether or not to ratify the
Treaty of Versailles (it ultimately did not), some Congressional
Republican Party members expressed their support for a legally binding US alliance with Britain and France as an alternative to the
League of Nations's and especially
Article 10's open-ended commitments; however, US President
Woodrow Wilson of the
Democratic Party never seriously explored their offer, instead preferring to focus on his (ultimately unsuccessful) fight to secure US entry into the League of Nations.
World War II and Cold War speaking in Berlin, 1987 ("
Tear down this wall!") with
Helmut Kohl, the then
Chancellor of Germany. Reagan was a committed Atlanticist. The experience of having American and Canadian troops fighting with British, French, and other Europeans in Europe during the World Wars fundamentally changed this situation. Although the United States (and to some extent Canada) adopted a more
isolationist position between the wars, by the time of the
Normandy landings the Allies were well integrated on all policies. The
Atlantic Charter of 1941 declared by US President
Franklin D. Roosevelt and UK Prime Minister
Winston Churchill established the goals of the Allies for the post-war world, and was later adopted by all the Western allies. Following World War II, the Western European countries were anxious to convince the United States to remain engaged in European affairs to deter any possible aggression by the Soviet Union. This led to the 1949
North Atlantic Treaty, which established NATO, the main institutional consequence of Atlanticism, which binds all members to defend the others, and led to the long-term garrisoning of American and Canadian troops in Western Europe. After the end of the Cold War, the relationship between the United States and Europe changed fundamentally, and made the sides less interested in each other. Without the real or perceived threat of the Soviet Union dominating Europe, the continent became much less of a military priority for the United States, and likewise Europe no longer felt as much need for military protection from the US. As a result, the relationship lost much of its strategic importance. The new democracies of the former
Warsaw Pact and parts of the fragments of the fractured
Yugoslavia took a different view, eagerly embracing Atlanticism as a bulwark against their continued fear of the Soviet Union's key now-separate great power fragment:
Russia.
21st century Atlanticism has undergone significant changes in the 21st century in light of
terrorism and the
Iraq War, the net effect being a renewed questioning of the idea itself and a new insight that the security of the respective countries may require alliance action outside the North Atlantic territory. After the
September 11, 2001, attacks, NATO for the first time invoked
Article 5 of the North Atlantic Treaty, which states that any attack on a member state will be considered an attack against the entire group of members. Planes of NATO's multi-national
AWACS unit patrolled the US skies, and European countries deployed personnel and equipment; however, the Iraq War caused fissures within NATO and the sharp difference of opinion between the US-led backers of the invasion and opponents strained the alliance. Some commentators, such as
Robert Kagan and
Ivo Daalder, questioned whether Europe and the United States had diverged to such a degree that their alliance was no longer relevant. Later in 2018, Kagan said that "we actually need the United States to be working actively to support and strengthen Europe". The importance of NATO was reaffirmed during
Barack Obama's presidency, although some called him relatively non-Atlanticist compared to predecessors. As part of the
Obama Doctrine, Washington supported
multilateralism with allies in Europe. The
Obama administration also enforced
sanctions on Russia with European and Pacific allies after the
2014 Russian annexation of Crimea. After his presidency, Obama also stressed the Atlantic alliance's importance during the
first Trump administration, indirectly opposing
Donald Trump in the matter. Kagan echoed common criticisms that Trump undermined the alliance. The importance of NATO in Europe increased due to the continuing threat of the Russian military and intelligence apparatus and the uncertainty of Russian actions in
former Soviet countries, among other disagreements such as trade disputes between the United States and the
European Union (EU). US President
Joe Biden emphasized multilateralism and the importance of international alliances, making the restoration and strengthening of the Atlanticist alliance a key priority. As the
Biden administration began, top officials of the EU expressed optimism about the Atlantic relationship. Following the February 2022
Russian invasion of Ukraine, journalists observed that the Russian aggression led to a united political response from the EU, making the defensive relevance of the Atlanticist alliance more widely known, and increasing the popularity of
NATO accession in countries like
Sweden and
Finland. Finland joined NATO on 4 April 2023 and Sweden on 7 March 2024. During the
second Trump administration, there were further tensions as Trump established the
Donroe Doctrine. In January 2026, while remarking on
Greenland crisis caused by US President Trump and his
proposed US acquisition of Greenland, Belgium's Prime Minister
Bart De Wever stated that eight decades of Atlanticism could be coming to an end. Trump’s pursuit of Greenland strained NATO, which had already been under pressure following a year of criticism and confrontational rhetoric from his administration. Speaking at the
World Economic Forum on 21 January, he directed some of his strongest remarks at European nations. In comments implying that the United States was indispensable to global security and economic stability, he stated, "Without us, most of the countries don't even work", and also joked about US intervention in World War II by telling the audience that without it they would "all be speaking German and a little Japanese". == Ideology ==