My biggest issue with her is her trip to Syria and how she handled the aftermath. She met with a murderous dictator without telling anyone and then lied about how the trip was funded. And before anyone says otherwise, its fine for the secretary of state to visit murderous dictators because they're the presidents top diplomat. Its not fine if a congressperson with no job in the administration does it.
For me, it's not so much that she met with him as it is the fact that she came back and regurgitated his propaganda. She was obviously only allowed to meet with Assad-approved Syrians while there, and then she comes back and says something like "I talked to the Syrian people, and all of them told me that there's no real difference between the rebel groups and they're all terrorists." (Not an exact quote, but that was the gist of it.) Does she even realize that meeting only with people in territory held by Assad is going to produce a skewed picture, or is she that gullible?
