Two of the main reasons for Truman's policy of containment during the Cold War were that the USSR was trying to rapidly expand, and that eliminating communism where it already existed was extremely unlikely. It was considered a very effective policy originally but then was viewed with skepticism when Vietnam hit.
Yellow journalism began after the Spanish-American war.
The spanish gov't favored the peninsulares over the creoles, often rewarding them with powerful gov't positions.
Rockefeller was not a failed capitalist