Answer:
President Truman established that the U.S. would be able to provide political, military and economic assistance to all of the democratic nations that are under threat from the external or internal authoritarian forces. In this light, the Truman Doctrine exacerbated the security concerns of the Soviet Union, and therefore stimulated an atmosphere of mistrust, which ultimately paved the way for the breakdown of the Grand Alliance in succmbing to Cold War hostilities.
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