The UDF/UHB demonstrations in the late 1980s traced their roots to the OPEC oil embargo of 1973 and the rude awakening it gave the USA to its vulnerability to internationally controlled oil supplies.

• 其实，之所以会出现80年代末的那场UDF/UHB昙花一现的展示秀，最早的起因是1973年欧佩克实施的石油禁运，以及美国对其受国际操控的石油供应影响的逐渐清醒。