The US has dominated Gulf energy security since the declaration of the "Carter Doctrine" in 1980. Under that doctrine, the US protected shipping during the Iran-Iraq war, expelled Saddam Hussein from Kuwait, invaded Iraq and now confronts Iran over the Strait of Hormuz.
But how long will a weakened US be content to play this role, when more and more of the Gulf's oil goes to rising powers in Asia?
Senior Gulf political and energy specialists debated this issue at the Brookings Doha Energy Forum last week. It is a timely question, with the US declaration that it would focus diplomatic efforts more on Asia counterpointing the Gulf tour of Wen Jiabao, the Chinese premier. That visit led to energy deals with Saudi Arabia and Abu Dhabi.
South Korea has already built up its position in the UAE with contracts to build nuclear power stations and to explore for oil. A Japanese oil concession was renewed and extended in 2010. And these three Asian powers, all major customers for Gulf oil and gas, have been prominent winners in bids for Iraqi field developments.
The next big prize is the Abu Dhabi Company for Onshore Oil Operations (Adco) concession in Abu Dhabi. It is currently held by major western companies including Shell, ExxonMobil, BP and Total but is due to expire in 2014.
Absent from this activity, surprisingly, is India. Indian companies have not yet been named in connection with the Adco renewal, and they did not win any bids in Iraq. Of the major Asian powers, India has the closest historical, cultural and personal ties with the region. It is a big customer for petroleum, and it would seem to be the best placed to assist with Gulf security.
But its national oil companies are relatively weak and, being poorer than its Asian rivals, it has been less able to offer the linked energy, loan and infrastructure packages that have been a distinctive feature of their outreach. India is unlucky with geography - tantalisingly close to Gulf and Central Asian energy but with the road blocked by hard-bargaining Iran, insecure Afghanistan and rival Pakistan.
The direct stake of Asian companies in Middle Eastern energy is still relatively small, certainly not in proportion to their consumption. For some time, Asian countries will remain content to have their energy assets protected free of charge by US forces.
But a speaker familiar with American diplomatic thinking suggested it was inconceivable that the US would continue to bear the entire burden while itself becoming more self-sufficient in oil and, especially, gas.
The EU, an apparently natural US ally and heavily dependent on gas from the Middle East and North Africa, has not shown signs of stepping up its role.
For its part, China in particular may eventually feel that its growing global stature requires a more active guard of its Gulf investments, people and energy supplies. This might happen in cooperation with the US - or in competition.
Indian observers in particular expressed the thought that the US has more often been a source of instability in the Middle East - a feeling that may be reinforced as oil prices rise over the confrontation with Iran.
And is the main threat to Middle East energy external - as the USSR was for Jimmy Carter - or disputes between regional heavyweights, Iran, Saudi Arabia, Israel, a more assertive Turkey, a revived Iraq or even Egypt?
It took a long time, and three major wars, to establish the US role after the withdrawal of British forces in 1971. The path to a multilateral security architecture, with more Asian representation, may be equally turbulent.
The Gulf states, including Iran and Iraq, are not passive bystanders in this process either. Each will be keenly aware that its choice of new energy partners is vital, not just for economic growth but for shaping the political arena for decades to come.
Robin Mills is the head of consulting at Manaar Energy and the author of The Myth of the Oil Crisis and Capturing Carbon
