Nuke, you can't even differentiate between incidental outbreaks of fighting such as in Somali and an overarching strategic imperative, so how can you expect to understand the subject?
US oil production is expected to be massively outstripped by consumption within the next 20 years meaning your oil imports will mushroom. Can you even begin to comprehend how economically screwed you would be as a country if the major oil producers started asking for payment in yen or euros or roubles instead of dollars? Couple that with a massive increase in consumption from the rest of the planet driving prices up even further. Is it starting to sink in yet how closely tied your fortunes are to the stuff?
Here is an example of how the control of oil was employed at a strategic level during the cold war. During the 1980's, the Saudi Arabian authorities along with their US oil industry partners colluded with the Reagan government to drive down the price of oil. Because gulf oil is the cheapest to drill on the planet, they were able to push down the price so low that it dropped below the level at which the Soviet Union with massive oil reserves of its own was able to make a profit on its own production. As a result, the Soviet economy was starved of hard currency. This was a major contribution to the fiscal collapse that signalled the end of the USSR.
Is it starting to sink in yet?
Why did the US encourage Iraq to attack Iran in 1980? Because the Iranian revolution had threatened to expand Iran's influence across the oil rich nations of the persian gulf.
Iran under Khomeni was pro-Russia. Carter initiated the assistance to the Afghan rebels for the same reason, to prevent Russian encroachment into the region and maintain the US strategic advantge.
Getting there yet? How about a picture?
What are all those bases in the Gulf for? Are they guarding the sand and the goats?