The following excerpt from last Sunday’s New York Times article “Obama Says Facts Support Accusation of Iranian Plot” hits at the core of what is meant by energy security, or more like insecurity in this case:
Even inside the Obama administration, some officials say they fear any crackdown on Iranian oil exports could drive up oil prices when the United States and European economies are weak. As one senior official put it, “You don’t want to tip the U.S. into a downturn just to punish the Iranians.”
So weak economies mixed with weak foreign policy (due to reliance on oil) lead to paralysis. Luft and Korin put it plainly in Turning Oil into Salt:
[Energy] independence means not having to kowtow to the various petrodictators that sit on the bulk of the world’s oil reserves. Independence requires that oil become just not that important anymore.