How does sectionalism affect economics today?

I believe the answer is: It Makes many people will focus only on their city or neighborhood rather than on the country as a whole.

Sectionalism refers to the act of loyalty that given to only specific region rather than the country as a whole. Because of this view, people tend to care on the general wellness of the people that they are familiar with (typically limited to the place where they grow up)

the colonial period, since this was a time of mass immigration from a variety of people from europe.