Article continues below advertisementDonald Trump has once again fueled dementia concerns while on his tour of East Asia. The president of the United States was speaking at a CEO lunch on Tuesday, October 28, during the Asia Pacific Economic Cooperation summit in South Korea when he forgot the name of Armenia - something he's done several times.Article continues below advertisementSource: MEGADonald Trump couldn't remember what countries he ended a war between.While bragging about how he's the alleged keeper of world peace, Trump couldn't remember what countries he had ended a war between.