From climate change to state breakdown, from inequalities in wealth to nuclear proliferation and Islamic militancy - as the global balance of power shifts from west to the east, what role can and should Britain play in a world faced by serious global challenges? To mark The World Tonight's 40th anniversary, Robin Lustig chairs a special debate on Britain's future role in the world with a panel of global experts at the leading foreign policy think tank, Chatham House. With Robin Lustig are Lord Hurd, former Foreign Secretary Dr Robin Niblett, Director of Chatham House Monika Griefahn, former German SPD MP Dr Stefan Halper, University of Cambridge Professor Kanti Bajpai, University of Oxford.