On this day 108 years ago, on April 24, 1915, the Ottoman Empire (now Turkey) began rounding up Armenian political and cultural leaders in Constantinople, marking the beginning of what would come to be known as the Armenian genocide. Over the next year or so, over a million Armenians would die — executed, murdered, or left to die of exhaustion and starvation. Many others would be exiled, losing their homeland forever. In the century since, the term “genocide” is still not universally applied to the Armenian tragedy, though support for that is growing. Turkey, meanwhile, insists what happened was not...