Does anyone know the exact reason of the Mexican loss in the US-Mexican War ?

Question

I have been reading about the Mexican-American War (1846-1848), and many sources had been quoted that the Mexican soldiers had poor equipment and leadership in the war. In addition, more US soldiers died from disease than battles. I wondered if this is acculate?

Answer 1

Scott's Campaign:
Scott marched westward toward Mexico City with 8,500 healthy troops, while Santa Anna set up a defensive position in a canyon around the main road at the halfway mark to Mexico city, near the hamlet of Cerro Gordo. Santa Anna had entrenched with 12,000 troops and artillery that were trained on the road, along which he expected Scott to appear. However, Scott had sent 2,600 mounted dragoons ahead and the Mexican artillery prematurely fired on them and revealed their positions. Instead of taking the main road, Scott's troops trekked through the rough terrain to the north, setting up his artillery on the high ground and quietly flanking the Mexicans. Although by then aware of the American positions, Santa Anna and his troops were unprepared for the onslaught that followed. The Mexican army was routed. The Americans suffered 400 casualties, while the Mexicans suffered over 1,000 casualties and 3,000 were taken prisoner.

In May, Scott pushed on to Puebla, the second largest city in Mexico. Because of the citizens' hostility to Santa Anna, the city capitulated without resistance on May 15. Mexico City was laid open in the Battle of Chapultepec and subsequently occupied.

Answer 2

The US soldiers pretty much just marched into Mexico City. The Mexican army was never that much to begin with and its leadership proved to be craven and without honor in Texas. The Mexican govt shot itself in the foot by "letting its bulldog mouth over ride its jaybird as/s", as it were.

Answer 3

They lost because their leader was outsmarted and would not listen to his generals advice.