Whelp, once again I'm going to go 'off the reservation' and disagree with the smart folks here, who clearly know more than me about this stuff. I will be praising the fedguv, so take notes.
In recent years, despite a massive increase in population, and a modest but measurable increase in the aggregate US standard or living - the US is using LESS petroleum each year. Note, that this is both less total volume of petroleum, and much less per-capita petroleum based on our rising population. Way to go US, patting myself on the back.
Now, some of this is due surely to cost. Like any commodity, as prices rise, economy plays a part in the equation, thus more Prius's on the road(Priui?), and fewer F350 crew cabs. Also, there has been continued aggregate efficiencies in all petroleum use cases. Now, as much as it pains me to admit - the fedguv has been at the vanguard of driving these numbers. Note, they don't get all the credit, but credit enough for honorable mention.
Lets look at our international counterparts, shall we? Russia(and psuedo-RS states). Have been increasing their annual petroleum consumption by massive amounts. Really, really big gains in the last decades, primarily driven by market forces as they migrate to a more capitalist friendly economy. More wealth, more Skodas, as it were. Their population increase has been modest, compared to the US so their per-cap numbers are also up. China - well, lets just use the word 'disastrous' and leave it at that. Population increasing and both per cap and aggregate petroleum use increasing rapidly. And why not? They make everything we used to make, and it takes oil to make stuff. So, I think the US is doing rather nicely WRT our oil consumption. So much so, that I got rid of my Prius, and bought -- a big truck! haha.
Oh, and as far as what OPEC does, while I thought everyone knew they were a production control mechanism, the fact is production quota is easily converted to price stability(or instability) in a commodity market like oil. So - if OPEC cuts production, prices inevitably rise and vice-versa, so production is really a proxy for the price of oil. BTW, the actual reason behind this is the way the oil market trades. All global oil trades are done in US dollars. So, since OPEC can't control the exchange rates of the dollar, they can(mostly) control the production quota, although plenty of members violate the quotas all the time, which is one of the major factors that leads to regular fluctuations in the (price) of oil.