How did the united states approach the negotiations with mexico?

The Mexican-American War begun when the Mexican troops condemned a cluster of U.S. soldiers in the uncertain zone. The United States professed warfare on Mexico since American military positioned in Texas were attacked by the Mexican military. The pronouncement of war was directed to the Congress for approval. 

the following best describes postwar era writers in their works:

many writers,authors,novelists,poets concentrated more on social art and social writing and stayed away from political writings.