Commemorating D-Day is crucial to remind us of the horror of war. That's the view of an historian who has spoken to FRANCE 24 about the fears that we are in a pre-war period with the threat of a third world war, and that this week's commemorations should be a wake-up call to the world. Curtis Young has spent years researching the African-American soldiers killed in World War I here in France, but his interest and enthusiasm to uncover the truth extend into the Second World War as well. He spoke to us in Perspective.