Gas in many countries is far cheaper than in the US, and the reason it is more expensive in others is heavy taxation and regulation, not lack of coercive negotiations.
Yes, the Iraq war had much to do with protecting the world oil supply. While the oil and gas industry is heavily subsidized, that war did not give the US a better deal on oil than anyone else. While it may have impacted oil prices, it did so globally.
Gas in many countries is far cheaper than in the US, and the reason it is more expensive in others is heavy taxation and regulation, not lack of coercive negotiations.