Final answer:
Several problems hindered the U.S. recognition of Texas, including the potential for war with Mexico, the contentious issue of slavery, and the cultural gap between American settlers and Mexican society. Despite these challenges, the U.S. recognized Texas in 1837, with Texas officially joining the Union in 1845.
Step-by-step explanation:
After Texas declared independence from Mexico and became the Lone Star Republic in 1836, several key problems hindered its recognition and annexation by the United States. Fear of inflaming tensions with Mexico was a significant concern as the addition of Texas could result in war.
Moreover, the issue of slavery was at the forefront; the annexation of Texas would disturb the delicate balance between free and slave states in Congress and provoke fierce debates similar to those over the Missouri Compromise. The burgeoning slave population within Texas conflicted with Mexican laws which were largely anti-slavery.
Additionally, Texas had a social and cultural gap with Mexico, as many settlers were not integrated into Mexican society, often rejecting Mexican law and the requirement to become naturalized Mexican citizens.
Despite these hurdles, Texas received recognition from the U.S. in March 1837, nearly a year after winning its independence. This recognition also came in the context of broader U.S. expansionist ambitions that included slavery, which was practiced in Texas.
Eventually, President Sam Houston secured a deal with President James K. Polk, resulting in Texas being admitted into the Union in 1845, which subsequently became a contributing factor to the Mexican-American War.