Rockefeller3.Beginning with a small oil refinery, this man‘s Standard Oil began to put competitors out of business.
The thing which was a major factor that threatened the major unity in the United States in the mid-19th century was:
<h3>The Great Depression</h3>
This refers to the period around 1929 in the United States which has a profound effect on the national economy.
This led to the failure of many banks, increase in unemployment and high deflation rates which all threatened the national unity.
Read more about Great Depression here:
brainly.com/question/441267
Robert S<span>. </span>McNamara<span>. Was the </span>secretary<span> of </span>defense<span> under Kennedy. He helped develop the flexible response policy. He was against the war in </span>Vietnam<span> and was removed from 1964 Congressional resolution that authorized President Johnson to commit </span>US troops<span> to south </span>vietnam<span> and fight </span>a<span> war against north </span>Vietnam<span>.</span>
