Having served in the military and having had a high-level security clearance, I find it unfathomable to think that a top general, one so highly respected as General Petraeus, would have gotten himself in such a compromising position with an extramarital affair. It's a violation of one of the first rules of security and a general violation of the Uniform Code Of Military Justice. A violation that "could" easily lead to being blackmailed in exchange for our nation's secrets.
This is actually a classic femme fatale trap that so many powerful men fall into. History is littered with them. Delilah. Salome. Mata Hari. Even Monica Lewinsky. It doesn't really matter if any state secrets are compromised in the process. The fact that Petraeus has had to resign is, in itself, a weakening of this country's security. Make no mistake about it, the General was a very important asset to this country. If he wasn't, he wouldn't have even been considered for the CIA leadership post. Sadly, this asset is now gone due to another femme fatale. This time, the femme fatale is Paula Broadwell; or, as the dictionary historically defines her: "an irresistibly attractive woman, especially one who leads men into difficult, dangerous, or disastrous situations..."