The declaration largely reiterated existing law, but dealt with many controversial points, including blockades, contraband and prize, and showed greater regard to the rights of neutral entities.
[2] The United States insisted that the belligerent nations fighting in World War I abide by the Declaration, while the British and Germans increasingly ignored it.
The British geostrategist and naval historian Sir Julian Corbett argued strongly against the provisions of the Declaration, which sought to outlaw 'general capture' of enemy commerce on the high seas during wartime.
[3] The arguments he set out gained currency within the Navy and British government, and would eventually prevail with Britain's decision not to ratify the Declaration and the successful waging of maritime economic warfare, including 'general capture', against Germany during the First World War.
In any case, the London Declaration was greatly deficient in referring only to surface ships and completely ignoring submarine warfare, which was to play a major role in both World Wars.