When Mexico achieved its independence from Spain in 1821, New Mexico became a province of Mexico, and trade was opened with the United States. ... Two years later, the Treaty of Guadalupe Hidalgo ceded New Mexico to the United States, and in 1853 the territory was expanded to its present size through the Gadsden Purchase.
Answer:
Tenth Amendment. The Tenth Amendment helps to define the concept of federalism, the relationship between Federal and state governments.
Explanation:
1. Histiography
2. Ideologies
3. Sources
It was built in to stop one branch of government from gaining too much power
