Explanation:
The main reason for this was slavery. The US did not want to annex Texas because doing so would have upset the balance between slave states and free states that had been accomplished with the Missouri Compromise of 1820. When Texas became independent, it wanted to join up with the United States.
The thing which was a major factor that threatened the major unity in the United States in the mid-19th century was:
<h3>The Great Depression</h3>
This refers to the period around 1929 in the United States which has a profound effect on the national economy.
This led to the failure of many banks, increase in unemployment and high deflation rates which all threatened the national unity.
Read more about Great Depression here:
brainly.com/question/441267
Answer:
Being near water, it was better land for farming. This created a large amount of food to promote trading.
Explanation: