What vision does santiago have when he witnesses the hawks in the desert?

The question refers to the book The Alchemist written by Paulo Coelho. Here while he was in the dessert, Santiago, seeing the hawks fighting has a vision, a glimpse that armies will ride through the oasis. The camel driver believes everyone can glimpse at the Soul of the World and takes Santiago's vision very seriously.

Image result for contextualize the Texas annexation.

Texas was annexed by the United States in 1845 and became the 28th state. ... The annexation of Texas contributed to the coming of the Mexican-American War (1846-1848). The conflict started, in part, over a disagreement about which river was Mexico's true northern border: the Nueces or the Rio Grande.