How can this document be used to justify american going to war with mexico

The war would help America spread democracy and "civilized" values into western lands. It would be good for the people in those areas. Also, if one did believe God had a plan for America, then war with Mexico was simply following through on God's wishes. Finally, if one believes in survival of the fittest among nations, then it might be seen as inevitable that the US would eventually control land to the Pacific

yellow fever and other tropical diseases

peasants’ war, (1524–25) peasant uprising in germany inspired by changes brought by the reformation, peasants in western and southern germany invoked   divine law to demand agrarian rights and freedom from oppression by nobles and landlords. as the uprising spread, some peasant groups organized armies. although the revolt was supported huldrych zwingli and thomas müntzerits condemnation by martain luther contributed to its defeat, principally by the army of the swabian league. some 100,000 peasants were killed. reprisals and increased restrictions discouraged further attempts to improve the peasants’ plight.

i think it would be " a" i might be wrong tho