In 1830, following an inspection by General Manuel Teran, the Mexican government decided to clamp down on American immigration to Texas in their Law of 1830. Austin described this as, "a lightening bolt out of the blue" because he saw it as a death blow to his colony. Austin saw his colonies future depending on a booming cotton economy that attracted American colonists (and slave labor). Without a steady flow of immigrants, Austin's colony could not grow. A further threat came about through Mexico's band of slavery that Austin was able to exempt Texas from. To make matters worse for Austin's colony, A Mexican general named Antonio Lopez de Santa Anna came to power after a 1833 revolution. Originally a liberal, Austin and other Texans saw Santa Anna as being a leader who could enact policies beneficial to Austin's Texas such as separate statehood from Coahuila. The second of two conventions in 1833 drew up a list of demands to Santa Anna's new government and elected Austin to travel to Mexico City to negotiate them with the Mexican government. Despite having his reservations with the actions of his fellow Texans, Austin traveled to Mexico City and made a case for their demands. However, the new Mexican government, preoccupied with other matters, didn't listen to Austin. Out of frustration, Austin wrote back to his fellow colonists telling them to seek separate statehood by their owns means independent of the government in Mexico. The letter was intercepted by the government in San Antonio leading to Austin's arrest on the grounds of treason. After a year in prison in Mexico, Austin became convinced that Texas could never prosper under Mexican rule. Austin returned to Texas in 1835 to find his fellow Texans' simmering anti-government sentiment. Santa Anna switched his loyalties from being a liberal Federalist to being a more conservative Centralist in favor of strong central government at the expense of the state. Santa Anna abolished the Federalist Constitution of 1824 and even abolished states within Mexico putting them under the command of military leaders. In response, Texas and other northern Mexican states began arming themselves for an invasion from Santa Anna and the Mexican Army. In Texas, the militia elected Austin as their general. However, because of his failing health, lack of military experience, and experience in diplomacy, Austin resigned his post after a few weeks to serve the Texas Revolution in other ways. With Sam Houston elected as general of the Texas Army, Austin was sent to the United States to solicit help for Texas against Mexico. Video courtesy of Texas Talks and the Texas State Historical Association.