When Nato last met in Britain in 1990 the Cold War was ending. As Margaret Thatcher and President Bush Sr pledged to continue to stand together, many might have thought that a new era of peace and prosperity would make this great security alliance less relevant. But today Nato is as vital to our future as it has ever been.

We meet at a time when the world faces many dangerous and evolving challenges. To the east, Russia has ripped up the rulebook with its illegal, self-declared annexation of Crimea and its troops on Ukrainian soil threatening a sovereign nation state. To the south, there is an arc of instability from north Africa and the Sahel to the Middle East. The growth of technology and