d) They didn't want to allow another slave state into the country.
Explanation:
The United States went to war against Mexico over the issue of Texas independence from Mexico, and subsequent annexation to the United States, a position that was supported by most of its inhabitants (including those of Mexican descent, also known as Tejanos).
However, the problem was that if Texas was admitted to the United States, it would become a slave state. The Eastern Part of Texas has the same climate and geography as Louisiana or Mississippi, and therefore, large slave plantations could be started there, and the annexation of Texas would then mean that the delicate balance between Free States and Slave States would break in favor of the slaves states. This is essentially what made Congress doubt about going to war with Mexico.
Civil wars. Probably the most important single cause of Byzantium's collapse was its recurrent debilitating civil wars. Three of the worst periods of civil war and internal infighting took place during Byzantium's decline.
Economic expansion demanded cheap labor, access to or control of markets to sell or buy products, and natural resources such as precious metals and land; governments have met these demands by hook (tribute) or by crook (plunder).
This is because with the plessy v furguson, and the Brown v Topeka schools, this was all segregation and it was accepted due to the "seperate but equal" mindset
