What are two reasons that H. G. Wells decided to include information about the establishment of the United States through the river steamboat and the railway?

H G Wells was one of the most well known writer of his time who used to write short stories and novels of almost all genres. Two reasons why H G Wells included information about the establishment of the United States through the river steamboat and the railway because:

The railway, steamboat, river, as well as the telegraph was all the part of America's development. Had Wells hadn't included them, then United states wouldn't have been this united. This was an essential part of America's unity. As we all know that Untied States is one of the most powerful country in the history of world countries. But it wasn't as powerful before as it is now, and without the existence of railways that wasn't quite possible.

to show how new transportation inventions were the leading cause in the rapid population growth

and

to show how the United States population has stayed uniform despite its growth