Petraeus scandal highlights military ethics concerns

CIA Director David Petraeus, testifies b
CIA Director David Petraeus testifies in January before the US Senate Intelligence Committee about "World Wide Threats." Petraeus resigned from his CIA position last week after it was revealed that he and his biographer, Paula Broadwell, had an extra-marital affair.
KAREN BLEIER/AFP/Getty Images

In light of the scandal surrounding Gen. David Petraeus, Thom Shanker wrote in The New York Times that "a worrisomely large number of senior officers have been investigated and even fired for poor judgment, malfeasance and sexual improprieties or sexual violence - and that is just in the last year."

Why is this happening and what's being done to curb it?