A Helgoland force on Germany's doorstep

With Helgoland in British hands, the Harwich Force's functions could shift forward to an island-based force. Destroyer flotillas and submarines could operate directly off the German coast while British mines complicated German plans for their own defensive fields. Britain might also install heavy coastal guns, potentially of 15- or 18-inch calibre, to cover the approaches. Germany would therefore have to plan a heavily supported assault against a defended position at the mouth of its own naval routes, rather than evade a distant patrol.