Iran today threatened to close the Strait of Hormuz if the United Nations imposes sanctions on Iranian oil as a response to Iran’s sketchy uranium enrichment program, according to a report from Reuters.

Iran has defiantly expanded nuclear activity despite four rounds of U.N. sanctions meted out since 2006 over its refusal to suspend sensitive uranium enrichment and open up to U.N. nuclear inspectors and investigators.

Many diplomats and analysts believe only sanctions targeting Iran’s lifeblood oil sector might be painful enough to make it change course, but Russia and China – big trade partners of Tehran – have blocked such a move at the United Nations.

Iran’s warning on Tuesday came three weeks after EU foreign ministers decided to tighten sanctions over the U.N. watchdog report and laid out plans for a possible embargo of oil from the world’s No. 5 crude exporter.

“If they (the West) impose sanctions on Iran’s oil exports, then even one drop of oil cannot flow from the Strait of Hormuz,” the official Iranian news agency IRNA quoted Iran’s First Vice President Mohammad Reza Rahimi as saying.

State Department officials suspect the threat could be an empty one — closing the Strait would, after all, hurt Iran almost as much or more as it would hurt importers of Iranian oil — but industry experts are divided about whether Saudi Arabia and other oil exporters would be able to supply the demand gap.

Meantime, the threat — empty or not — underscores the persistent need for the United States to assume energy independence. As a reminder, energy independence has become less a question of capability than of policy. According to a report from the Institute for Energy Research, the United States has 1.4 trillion barrels of recoverable reserves of oil — or more than the entire world has used in 150 years. That’s enough to fuel the United States for the next 250 years. Natural gas and coal resources are in even greater abundance. Energy independence could really and truly be as easy as 1-2-3. A sensible policy would (1) unlock more federal lands, (2) develop shale resources and (3) eliminate excessive regulation. But energy independence is not only a clear-cut proposition, it’s also a one-two punch: It’s a positive from a foreign policy perspective and it’s a positive from an employment perspective. According to the same IER report, taking basic steps toward energy self-sufficiency could create up to 1 million jobs. It really does seem like a no-brainer to me.