The Marine Corps has a zero-tolerance policy on substance abuse. Just like drugs, alcohol physically impairs the body to perform to its fullest capabilities. Drinking and driving not only puts the driver at risk, but the passengers and other motorists in danger as well. (U.S. Marine Corps photo by Cpl. Jonah Lovy/Released) - The Marine Corps has a zero-tolerance policy on substance abuse. Just like drugs, alcohol physically impairs the body to perform to its fullest capabilities. Drinking and driving not only puts the driver at risk, but the passengers and other motorists in danger as well. (U.S. Marine Corps photo by Cpl. Jonah Lovy/Released)