Though shifts in demand and reduced production by some major producers have influenced oil prices, investor behavior is also increasing market volatility.

The Gulf of Mexico oil spill spotlights the growth of deepwater drilling and the challenges of balancing strong environmental regulation with efforts to expand U.S. domestic oil production.

Non-OPEC oil producers, which turn out most of the world’s oil, are operating near capacity.

Political volatility among the world’s leading oil producers suggests deeper causes for recent price spikes.

Despite eroding public support for the Iraq war, troop morale remains high. Experts warn that could change as U.S. forces get further bogged down in Iraq.