First, the weapons should be intended for use only in retaliation after a nuclear attack. Second, the possession of the weapons must be a temporary expedient.

首先，这些武器应当只在遭受核袭击后反击时才使用。其次，这些武器的拥有必须是一种临时的应急手段。

《柯林斯英汉双解大词典》

President Barack Obama told delegates Tuesday that the risk of a nuclear attack has risen.

奥巴马对星期二前来的代表们说，核袭击的风险已经在上升。

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Sagan makes the point that the most dangerous collision facing us now, however, is one that might be mistaken for something else: a nuclear attack.

萨根阐述的观点是目前我们面临的最危险的是碰撞而非人们误解的核战。

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In a real nuclear attack, hundreds of thousands of people would have to be decontaminated from radiation.

VOA: standard.2010.07.21

Today's nuclear threat differs from that of the Cold War, according to U.S.Secretary of State Hillary Clinton, "The threat of nuclear war, nuclear attack that we grew up with in the Cold War has diminished.

VOA: standard.2010.04.11

He is expected to press Israel not to carry out its threat to attack Iran's nuclear facilities.

VOA: standard.2009.07.26

Jeong Kim, 39, is a former Navy officer who spent seven years aboard nuclear attack submarines.

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Advocates of Mutual Assured Destruction insisted on leaving civilian populations totally vulnerable to nuclear attack.

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Then, aiming upward, you can shoot out of the water like a nuclear attack sub.

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