is there some reason that shale oil
only exists in North America?
is shale oil existed worldwide,
the Arab hegemony would be broken
Oil shale is not exclusive to the U.S.A.
I believe it requires specialized equipment to find it, however.
Shale oil and gas are plentiful throughout the world’s energy basins. China, Europe, and Argentina have huge resources. The problem is the infrastructure. To develop on a massive scale, you need roads, pipelines, and processing facilities. You also need some economic sanity (Europe has effectively banned hydraulic fracturing, which is the only way to unlock the hydrocarbons). Major oil service companies must be set up with yards, equipment and personnel - this alone will take years to establish overseas. You need the right kind of proppant (spherically-grained white sand works best, found exclusively in the upper Midwest of the U.S.).
All of these are up and running in the U.S., which is why we are the front lines of the unconventional resource revolution!