The Kriegsmarine had to be virtually rebuilt after the First World War. Forbidden to own capital ships and submarines, Germany nibbled away at first one clause of the Treaty of Versailles, then another, until a powerful navy force existed. At the outbreak of World War Two, relatively few capital ships were in commission, and no aircraft carriers. There was never any prospect of matching Britain in terms of capital ship numbers, but the qualitative advantage of the proposed super-battleships might have made a considerable difference. In any case, the Kriegsmarine was not a navy designed to tackle a major fleet head-on in fleet engagements. Instead, it was a commerce raiding force. German capital ships were built according to principles tried out in World War One; internal compartmentalisation and damage control measures made them very difficult to sink, while their efficient power plants ensured a good top speed, essential in a raider.