Trump says border wall will stop drug flow. Is that true? -- PolitiFact

President Donald Trump claims his promised border wall with Mexico will stop drugs from coming into the United States and help solve the nation's drug epidemic. More than 64,000 people died in 2016 from drug overdoses, the majority of which were linked to opioids, according to the Centers for Disease Control and Prevention. ....
http://www.politifact.com/truth-o-meter/article/2017/oct/26/will-border-wall-stop-drugs-coming-united-states/