Diplomatic Resolution Quotes
The Germans wanted war with Serbia and used the dispute between Austria and Serbia as an excuse to mobilize and go to war ostensibly to protect their ally, the Austrian Empire, from the Serbs who they knew would be likely supported by Russia which had traditionally supported their fellow Eastern Orthodox against Roman Catholic or Protestant enemies. Russia still tends to protect and support the Serbs. This statement was one of the many that showed that Germany was the major aggressor in the First World War and therefore had to pay reparations to France and others.
The Navy and the foreign office had to find the argument to support the action; it was anxious work.
Early in the first world war, the British "extended" the traditional legal concept of a blockade: