Why did americans "dream" of linking the atlantic and pacific ocean bg rail, as thw author states?

Linking two continents together through a railway is called the Transcontinental Rail System. Americans wanted this to happen because they wanted to explore the beauty and riches of the Pacific. It would open up unhabited areas of the continent. Open up opportunities for trade and commerce. It would allow them to explore for resources that they can tap into. The transcontinental rail would make trade and travel easier and more accessible.