It is a global market for oil. The US exports and imports oil of different types. The only way you could have a separate price for the US market is to decouple US oil from the global market. However, that would require significant investment into the refining infrastructure by the oil companies, which wouldn't make sense for them at the reduced profit margins compared to the global markets. If anything, that would actually encourage oil companies to invest elsewhere on the globe and devest from the US. The "lite" version of this was tried during the 1970s oil crisis and it was a financial disaster.
If you want US oil production decoupled from the global oil market, then it would require the federal government to seize and fully nationalize the entire oil market like it were the US Postal Service, which could potentially result in cheaper gas prices for the US after proper investments were made into infrastructure (which would take several years) , but would make the US the economic pariah of the entire world.