Final answer:
General Santa Anna's mistakes at the Alamo included high Mexican casualties due to his attack strategy, and executing prisoners which galvanized Texan resistance. His subsequent capture at San Jacinto and the controversial treaties of Velasco left the Texas issue unresolved.
Step-by-step explanation:
The mistakes made by General Santa Anna at the Alamo encompass several strategic and humanitarian blunders. His decision to attack the Alamo with repeated waves of troops led to high Mexican casualties, showing a costly disregard for the lives of his soldiers. Moreover, Santa Anna's choice to execute Texan prisoners and noncombatants was seen as ruthless and contributed to the determination of the Texans to continue fighting. This action, along with his execution of prisoners after other defeats such as Goliad, helped to galvanize the Texan resistance and may have ultimately contributed to his defeat and capture at the Battle of San Jacinto.
Strategically, Santa Anna's efforts to intimidate the Texans through brutality had the opposite effect, strengthening their resolve. The public and private treaties of Velasco that ended the hostilities were signed under duress, as Santa Anna was a prisoner, which led the Mexican Congress to refuse to acknowledge them after he was deposed, thus leaving the issue of Texas unresolved.