Be aware that the numbers in the graph include Natural Gas Liquids (but not crude oi). Some data sets at EIA separate out the NGLs but some do not.
I don’t like including them when discussing oil and transportation fuel. The NGLs have changed too much lately and can distort where the difference is.
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When you click to the graph at the eia site — it shows that the USA has gone net positive for net petroleum imports. I’m not getting that unless that has something to do with NGLs as you seem to be alluding. (There has been a huge surge in NGL’s in the last couple years as their prices have remained relatively high unlike natural gas.)
Not all petroleum (including crude oil), only petroleum products.
Click on the following link for more info
http://www.eia.gov/dnav/pet/pet_move_neti_a_EP00_IMN_mbblpd_m.htm
Under the red “U.S. Net Imports by Country” is a pick box for changing what is included in the data. What was included in the graph I had was “products”. But if you look at “petanes plus” and “Liquified Petroleum Gases” you will see they are less than half the net export.
We bring in more crude oil than we need for our own use. We refine it, the export the surplus products we don’t consume. That include heavies (refinery leftovers) like petroleum coke and residual fuel oil. We also export a lot of diesel to countries that use a higher gasoline to diesel rate than we do.