Wont be able to ban it, but getting it out of public libraries and schools would help. Used to be “porn” was only available in back alley shops.
It's available on any phone or computer with an internet connection.
One place I was stationed in my career was this Air Force Base located in a smallish city in central Georgia. There were several strip clubs near the town but only one within the city limits. The town was constrained from forcing the club closed because the club allegedly assiduously complied with all the city's ordinances and so they had no legitimate way to close it that would stand up in court.
The way they finally got rid of it was when the local newspaper posted a photographer outside the entrance every evening. He took candid photos of each and every patron exiting the club. A selection of those photos were prominently featured in the newspaper. Eventually men were scared to go as they were afraid of their portrait showing up...they were afraid not only of their spouses seeing the photo, they were also afraid of their church congregations seeing it as well as women they worked with.
After only a month or so, the club decided to move to a new, improved location in the county. Seemed like nobody cared about what went on in the county, just as long as it wasn't going on within the city limits. Go figure.
If they decide to ban porn in the US, the porn distributors (websites) will just move from within the city limits to "the county" (using the above analogy). Won't accomplish anything but it will make somebody feel good because they "did something".