Final answer:
Mexican historian Juan Brom believes that Mexico lost the war due to the Treaty of Guadalupe Hidalgo and American greed.
Step-by-step explanation:
Mexican historian Juan Brom believes that Mexico lost the war due to several factors. One of the main reasons is the Treaty of Guadalupe Hidalgo, which resulted in Mexico losing more than half of its territorial land mass to the United States.
Additionally, Brom argues that the United States deliberately provoked the war and that American greed was the primary underlying cause. This perception led to lasting distrust and suspicion towards the United States in Mexico and much of Latin America.
Furthermore, the war upset the balance established by the Missouri Compromise and reignited the slavery debate, threatening the stability of the United States.