HOUSTON

EVER since the Arab oil embargoes in the 1960s and 1970s, American presidents have pledged to end the country’s dependence on foreign oil by drilling more at home and increasing energy efficiency. But “energy independence” was little more than a dreamy campaign slogan.

Now, suddenly, the dream looks to be in reach. The International Energy Agency reported this week that the United States was poised to become the world’s biggest oil producer thanks to new drilling technologies in shale fields across the country. With oil production going up each month, not only are imports from the Organization of the Petroleum Exporting Countries going to drop, the energy agency predicted, but the United States will also become a net oil exporter by 2030.

At first look, the changing energy panorama seems implausibly fortuitous, and it is no doubt a strategic game-changer. But the report also warns that the global energy future is still full of challenges, and many energy experts say any celebrations should remain muted.

Even if the United States were no longer dependent on oil from the tumultuous Middle East and North Africa, vital American trading partners like China, India, Japan and Europe would continue to import increasing amounts of oil from the region. Future price shocks at the pump would still be likely as long as the world depended on unsteady producing nations like Venezuela, Nigeria, Iraq, Libya and Iran, where politics often mixes inharmoniously with crude.