1. Economic ties
The border states had closer economic ties to the North than the deep south states. They were more reliant on Northern markets for their agricultural products, and they had more industrial development than the deep south states. Secession would have disrupted these economic ties and caused significant economic hardship in the border states.
2. Political ties
The border states had stronger political ties to the Union than the deep south states. They were more likely to have Unionist sympathies, and they had more representation in the federal government. Secession would have meant giving up this representation and losing influence in the national government.
3. Fear of Northern retaliation
The border states were aware that the North was much more powerful militarily than the South. They feared that if they seceded, the North would invade and devastate their states. This fear was a powerful deterrent to secession.
4. Slavery
Although the border states were slave states, they were not as dependent on slavery as the deep south states. They had smaller slave populations, and they were more diversified economically. This meant that they were less likely to see secession as a necessary means of protecting slavery.
In conclusion, there were a number of factors that influenced the decision of the border states not to secede from the Union at the same time as the deep south states. These factors included economic ties, political ties, fear of Northern retaliation, and the issue of slavery.