Their Aegis missile defence system, deployed to protect American carrier groups, is designed to track a missile's trajectory from launch.

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The ability to perform such a feat means that, if necessary, it will be possible to try to intercept an attacking missile at several points along its trajectory.

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By tracing the trajectory of the Palestinian missile within the first few seconds of its flight, the system could calculate whether or not it was heading for a populated area and therefore whether the firing of a defensive interceptor missile was necessary.

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However, its baseline version of the interceptor is already quite capable, which is why the Navy will conduct a test this spring to see how it fares against a Trident ballistic missile flying a longer, faster trajectory than the service currently is postured to counter.

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He asserts that even if a missile interceptor succeeded in effecting a boost-phase "kill" on an incoming missile (that is during the early stage of its trajectory when it is moving relatively slowly, easily identified and vulnerable to destruction), its warhead might continue on and land in friendly territory with devastating effect.

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