We must not turn our backs on a European Union that has helped us keep the peace since the dark days of the Second World War and which, working together, has a better chance of staving off the threat from terrorism. Only by working together in Europe can we avoid something terrible happening this century. Which is why I've called my campaign 'Stand Up For Europe'. And that's what I'll be doing for 31 days in 31 cities, starting 23 May in Birmingham. Because I believe that no vote in our lifetime has ever been this important.