Whereas, following World War II, the United States rejected isolationism, established its role as a world leader, and developed an international alliance system that protected the United States while supporting democracy, freedom, and economic prosperity with European nations; Whereas, 70 years ago, the United States announced the Marshall Plan for Europe, a strategic investment in Europe, as well as articulated the Truman Doctrine, which sought to contain a growing Soviet threat in Southern Europe; Whereas, in 1949, the United States, Canada, Belgium, Denmark, France, Iceland, Italy, Luxemburg, the Netherlands, Norway, Portugal, and the United Kingdom signed the North Atlantic Treaty that formed the basis of the North Atlantic Treaty Organization (in this preamble referred to as NATO ); Whereas NATO was created to protect countries from a growing Soviet threat, promote international peace and stability, and defend freedom; Whereas, to date, 28 countries have joined NATO; Whereas, for more than 67 years, NATO has served as a central pillar of United States national security and a deterrent against adversaries and external threats; Whereas NATO continues to improve its collective defense measures, enhance its military capabilities to address a full spectrum of complex threats, and partner with non-NATO countries to promote international stability; Whereas Article 5 of the North Atlantic Treaty is an integral part of NATO and states that [t]he Parties agree that an armed attack against one or more of them in Europe or North America shall be considered an attack against them all … ; Whereas NATO invoked Article 5 for the first time less than 24 hours after the September 11, 2001, terrorist attacks against the United States