For most conservatives, the Cold War was a necessary evil.

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Experts are already pointing to the build-up to the first Gulf War in 1991 when President Bush senior - while insisting such a resolution was not necessary - did indeed seek and obtain congressional support for the war to oust Iraqi troops from Kuwait.

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Mr Obama will be incandescent if Israel provokes a war which he has said is not yet necessary, and on the eve of an election.

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But German Defence Secretary Franz Josef Jung has defied calls to resign over the incident - the deadliest involving German troops since World War II - and a defence ministry spokesman insisted the decision to attack was "militarily necessary and correct".

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And I would require some accountability that I don't think that we have had, and do a thorough review of what was necessary and how we can make the transition that we haven't yet made from a Cold War apparatus to the world we live in today.

CENTERFORSECURITYPOLICY: Center For Security Policy

Under the strategic circumstances of the Cold War between the Soviet Union and the United States, all that was necessary was to ensure the survivability of nuclear forces because very little could survive on the ground should a nuclear war erupt.

CENTERFORSECURITYPOLICY: Center For Security Policy