It's not just oil, it's heavy crude oil; the type US is equipped to process, and rapidly running out of.
a nice visual in support of your comment
https://www.visualcapitalist.com/all-of-the-worlds-oil-reser...
alt Hacker News
a nice visual in support of your comment
https://www.visualcapitalist.com/all-of-the-worlds-oil-reser...