The United States adhered to a policy of ISOLATIONIST after World War I.
After the war ended in 1918, America decided to adopt an isolationist policy, which had been previously interrupted due to the war. The U.S. wanted to stay out of global affairs, avoid political or permanent economic/politic alliances that didn't serve their interests, including entering the League of Nations, international cooperation first proposed by the American President Wilson.
Instead, the U.S. focused on domestic issues such as business growth, industrial expansion, imposing of tariffs on imported products, among others.
The Suez canal crisis