hahahha that would certainly have an impact, but it doesn't take things that drastic.Not unless he starts a major war or shuts down the Suez Canal.
The oil industry, like any other industry, is going to react to Govt action, and even action they believe might happen. Companies don't like being caught reacting if they can help it. If someone comes into office with promises to shut down certain things, tax the heck out of certain things, etc, a business will react before that happens.