Colonel Ethan Allen Hitchcock/U.S. Naval Officer

I am a professional soldier, graduate if the U.S. Military Academy, commander of the 3rd Infantry Regiment. I am an aide to General Zachary Taylor. Like President Polk, Taylor wanted wanted a war with Mexico, so he moved troops to the Rio Grande-- territory claimed by both Mexico and Texas-- to provoke the Mexicans. Eventually, the Mexicans did attack, as Taylor and Polk knew they would l. And now U.S. leaders have their war. The United States doesn't have any right whatsoever to move into Mexico. The government is looking for war so that it can take over as much of Mexico as it wants. The United States is the aggressor. My heart is not in this war. But I am an officer in the U.S. Army and I must carry out my orders.

http://www.historyisaweapon.com/defcon1/hitchcockdiary.html

From the diary of Hitchcock, recounts on the days of June 30, 1845 to March 26, 1846 speaks of Hitchcock's view from the invasion of Mexico. He describes the event with as much detail as possible, yet from his point of view, this invasion has no grounds to happen and itself describes the repulsion Hitchcock has towards these efforts. He also talks mentions the two main forces behind the war with Mexico: Polk and Taylor. They are the main ones who push for the invasion.

I'm a luck man. I got to sail into California to seize that territory for the United States of America. Its our a now, not the Mexicans'. Here's what I wrote in my diary when I sailed up from South America and landed in Monterey, California: "Asia will be brought to our very doors. Population will flow into the fertile regions of California. The resources of the entire country will be developed. The public lands lying along the route if railroads will be changed from deserts into gardens, and a large population will be settled." This is where I'm going to settle after we defeat the Mexicans once and for all.

http://memory.loc.gov/cgi-bin/ampage?collId=llsl&fileName=009/llsl009.db&recNum=975

The Treaty of Guadalupe Hidalgo was a treaty that designated the Rio Grande as the borderline between the two countries of Mexico and the United States. It was signed by the countries on February 2, 1848 and officially ended the Mexican War. Mexico was paid 15 millions dollars in exchange for new territory that included California, Texas and Nevada.