The U.S. is drawing plans for airstrikes against Iranian targets as a "last resort" to prevent Iran from developing nuclear weapons. The most likely strategy would involve aerial bombardment by long-distance B2 bombers, each armed with up to 40,000lb of precision weapons, including the latest bunker-busting devices.
They would fly from bases in Missouri with mid-air refuelling.
Iran nuclear facilities that could become targets
Saghand - mining: Uranium ore discovered 1985. Mining began later that year with 120,000 tonnes of ore yielding some 50-60 tonnes of uranium annually.
Ardkan - milling: Ore is purified to uranium ore concentrate, also known as yellowcake.
Gehine: Mine and milling facility which will produce 24 tonnes of yellowcake annually.
Isfahan - conversion: Yellowcake is cleansed of impurities and converted to uranium hexafloride gas, cooled,and condensed to a solid known as hex.
Natanz - enrichment: Pictures published in the Sunday Telegraph reveal new buildings at site which can be used to produce weapons grade uranium.
Teheran: Enrichment facility at Kalaye dismantled. Research reactor and radioactive waste storage facilities still operating.
Bushehr: Russian light water reactor is due to start up this year. Can produce reactor-grade plutonium.
Arak: Heavy water research reactor - better suited for weapons-grade plutonium production.
Anarak: Waste storage site.
The review of the Pentagon's contingency plans follows the stream of recent discoveries of Iran's secret nuclear operations and the virulent rhetoric of President Mahmoud Ahmadinejad since he was elected last year. Iran is still thought to be anywhere between three and 10 years away from physically producing a nuclear weapon.