The obama administration endorsed state-centered federalism by:

The answer to this question is permitting states to set higher fuel economy and emissions standards than the federal government.
By giving this permission, the central government has a lot more room to create policy that would affect the situation in the private sector. Including creating several benefits for certain companies to give them competitive advantage in the market (which may deem as unfair by other companies)

The transcontinental railroad provided a means of fast transportation. it cut a 6 month trip into 6 days, created jobs for many people and encouraged immigration. the homestead act played a huge role in western expansion; it allowed settlers to begin a fresh start, and gave them land in exchange for their residence for up to five years and a small fee.