Describe the Mexican American war

The Mexican-American War was a conflict between the United States and Mexico, fought from April 1846 to February 1848. ... It stemmed from the annexation of the Republic of Texas by the U.S. in 1845 and from a dispute over whether Texas ended at the Nieces River (the Mexican claim) or the Rio Grande (the U.S. claim)

Explanation:

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."