The United States become a global power following the conclusion of WWII. It helped create and oversea international institutions and alliances, such as the United Nations and NATO. It took a more active role in the affairs of countries around the world, and maintained a huge military, rather than downsizing after the war ended.
These actions helped to ensure peace in Europe, but also led to many interventionist wars around the world, such as Vietnam, Iraq, and Korea. It has also led to the United States being in serious debt, largely due to our intense military obligations.
1The power of the Executive Branch is vested in thePresident of the United States, who also acts as head of state and Commander-in-Chief of the armed forces. ... Fifteen executive departments — each led by an appointed member of the President's Cabinet — carry out the day-to-day administration of the federal government
U.A.E got it's independence on 2nd December 1971.
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Because they were stronger united than they were divided, and being weaker they were susceptible to attacks