You mean they would lower the price of oil to compensate for the reduced demand. They could do it too. Saudi oil is extracted for about five bucks a barrel.
But North America already has the oil resources and the technology to produce oil for at least the next 100 years if the price goes high enough.
With the current state of the world economy i.e. strong growth and high demand for petroleum products, I believe that if America cut it's demand for OPEC oil, currently at 16% of our use, OPEC would be able to raise prices to make up for part of the revenue shortfall. India, China and the other heavy users would pay the price simply because they need the product. It would be a balancing act for OPEC to keep the prices low enough to sustain the worlds economic growth yet high enough to make up for the income loss from America not purchasing from OPEC any longer. If they push it to high the worlds economies slide into recession and nobody will need their oil, at least not much of it. I realize this flies in the face of the market mechanics of supply/demand but it just may work.