Answer:
With the treaty of Guadalupe Hidalgo United States finally encircled their territory on the west, thus fulfilling the goal to spread it to the Pacific.
Explanation:
This peace treaty was signed in 1848 and allowed United States to gain new territories on the west, thus finishing their spreading towards the Pacific.
More than 500 thousands miles were added to United States, including parts of present-day Arizona, California, Colorado, Nevada, New Mexico, Utah and Wyoming.
