Because you want to hurt the US refinery business and put an end to our refining surplus capacity and the associated jobs?
Do not look for the government to help any business. The best they can do is get out of the way.
It builds in a $10/bbl advantage for domestic producers selling into the US market, which remains the largest market, and builds in a durable $10/bbl disadvantage for overseas suppliers. Naturally the oil would still flow in to cover what the US can’t (yet) produce, and the US gov’t would still collect about half that tax revenue that it does now. As you said though, the gubmint will still have to get out of the way, open up exploration as well as production in places like the ANWR. Since the import tax would be on any petroleum, crude (which is the lowest cost) would come in, and have to be refined here. As the petrodollar supply shrank in foreign countries, the value of the dollar would go up, and *that* would have a longer term negative impact on US petroleum production.