What is the concept of " going public "?

no statements but ok.

the statement that best describes the idea of manifest destiny that was used in the 19th century would be that "it was fate that the united states would continue to  expand westward," since people thought the us was "destined" to do so. 

he sent troops to protect the students as they entered the school.

a social contract.

"a social contract is an agreement between citizens and their leader where the citizens give up certain freedoms in exchange for protection. the constitution of the united states is an example of a social contract."

to reform the distraught soviet union, the democratization of the communist party was promoted through party secretary mikhail gorbachev's policies of “perestroika” and “glasnost.” perestroika refers to the reconstruction of the political and economic system established by the communist party.