How oil's become the world's most potent weapon. Daily Mail

How oil's become the world's most potent weapon: Forget nuclear arms. The U.S. and Saudis are behind an oil price crash that could topple regimes in Russia and Iran

1.      Price of oil has fallen dramatically - down by nearly half in six months

2.    The collapse in price means it is cheaper to fill up your car at the pumps

3.     But has sparked fiscal crisis that threatens to shift global power balance

4.    U.S. and Saudi Arabia are using market slump to wreak havoc on enemies

5.     While Russia - which depends on a bouyant price - is on the edge of crisis

6.     Most pressing issue for Britain is the fate of oil industry in North Sea basin

From Russia to America, and from Scotland to the Middle East, the dramatic fall in the price of oil — down by nearly half in six months — has sparked an economic crisis that threatens to shift the global balance of power in dramatic fashion.

As Russia teeters on the edge of crisis, America and Saudi Arabia are using the depressed oil market to wreak havoc on enemies such as Iran. The repercussions are being felt closer to home, too, with the North Sea oil industry described as being close to collapse.

The good news is that it’s cheaper to fill up your car at the pumps, but what does it mean for Britain’s national security?

Here, the Economist magazine’s Energy Editor EDWARD LUCAS offers a simple guide to these deeply turbulent times.

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