The Mars class was unusual at the time in being designed from the keel up as a Navy ship; most of the service's earlier logistics ships were adapted from commercial designs.

该火星级船舶是不寻常的，它被作为海军舰艇从龙骨开始设计的，很多早期后勤服务的船舶适合商业设计。

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The Zumwalt class DDG 1000 destroyers designed from the keel up to handle this and future threats, now will be limited to three ships without a ballistic missile defense capability.

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