What idea prompted the United States to try and claim New Mexico?

Labor groups in the united states suppored the homestead act of 1862 because this act

By the end of the 1800s, there was a change in the nature of the immigrants coming to the united states. immigration from northern europe—england, ireland, germany, and scandinavia—declined, while immigration from italy, russia, and austria-hungary grew. in fact, between 1900 and 1910, more than three-fourths of all immigrants came from these three countries. unfortunately, these countries were far removed england, the home of our founders, and the immigrants who came from them had a hard time adjusting to life in their new country.

How did political revolutions in the atlantic ocean basin affect or alter the institution of slavery and the lives of slaves