Of course you're going to have a higher supply of oil, look at the price of the stuff!
EDIT - the other factor is the more interesting one. I wonder how much it costs to insure millions of dollars worth of oil and tanker through the Strait of Hormuz? I wonder how much it cost before Operation Iraqi Freedom?
EDIT #2 - Found a nice article by the author of
OilShock -
http://www.telegraph.co.uk/opinion/m.../03/do0311.xml
in the process of reading it, thought it was relevant