Uncertainty in Iraq's oilfields is driving crude prices higher.  Some 

American companies are evacuating their workers.  Houston Oil and Gas Journal Editor Bob Tippy says most of the fighting is in northern Iraq, while most of the crude production comes from the south.

“The older production around Kirkuk Field, has been offline since March,” Tippy explains, “because the export pipeline that handles that production through Turkey has been blown up, again.  That's kind of a common occurrence there.”

Despite the worries about violence, production in southern Iraq has actually increased in recent days.  If the fighting gets worse, more companies may evacuate more American workers.

“There may be, in some cases, the ability to sustain production with local folks, you know, keep things flowing,” Tippy says.  “But, I would assume we will have to expect some slowdown in production.”