Dempsey said that "this challenge didn't accumulate overnight, and it won't be solved overnight".
The US Air Force and the Navy, in the last few weeks, have disclosed investigations of cheating on tests by officers and sailors involved in nuclear operations. The Air Force also is pursuing a drug use investigation, and sexual assault and harassment cases have surfaced across the services.
"Acts of crime, misconduct, ethical breaches, command climate and stupidity each require a distinct solution," he said. "But the overall solution is attention to who we are as a profession. And that's my focus."