[[Image:SDI.jpg|thumb|right|100px|Extended Range Interceptor (ERINT)]]
[[Image:SDI.jpg|thumb|right|100px|Extended Range Interceptor (ERINT)]]
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Ground-based systems must be able to detect a rapidly-approaching ballistic object, and destroy or divert that object well enough to avoid catastrophic damage to the target.
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====Space-based systems====
====Space-based systems====
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Space-based systems generally aim to destroy a ballistic missile at the height of its trajectory.