The given illustrations or events are adequate to prove that the Mexican-American War (1846-48)was an effort to extend the American territories, and it shows the horrific imperialistic attitude of the United States. Can you give me a response to the points brought below?

1) The philosophy of 'Manifest Destiny' was coined through John Sullivan, the editor of the Democratic Review. This word was pampered by United States as an excuse to usurp territories from its neighbors and extend its empire from Atlantic to the Pacific.

2) Texas was annexed to the United States as the 28th state despite of the opposition of Mexico.

3) President Polk took office with the agenda to annex California and, even before any act of aggression; he noted the cabinet concerning the possibility of war with Mexico.

4) American invasion on the Southwest was a plan to expand slavery even to the territories of Mexico. Most of the generals who led to the war were slave owners.

5) The general mood within the country was against annexation.