During the Cold War, and in the past decade, U.S. policy often viewed nuclear weapons apart from the rest of the U.S. military establishment, with nuclear weapons serving to deter a global nuclear conflict with the Soviet Union or Russia.
Answer:
the Texans had religious motives to annex themselves. The Mexicans had forced the American immigrants to convert to Roman Catholicism, effectively revoking the freedom they held in the United States.
It was trench warfare that was used to a great extent in World War I. This led to a significant elongation of the conflict, since targeting soldiers was much harder.