Henchmen

The BBC report of the bombing that killed three members of the Syrian inner-circle referred to the victims as "Assad's henchmen." What a great word. It comes from the term horseman, or nobleman's aid who would help with the horses, but it has come to have a completely negative connotation. For Assad to even have henchmen instead of, say, aids, underlings, or associates, means he must be evil. Good people or those who are morally neutral are not said to have henchmen. Henchmen help carry out nefarious plots. But how bad does one have to be to have henchmen? If I assign two friends to look out for the authorities whilest I intentionally jaywalk, are my compatriots henchmen? Does it have to be an organized group of wrong-doers with an intent to maintain the structure? Is it a matter of the degree of harm intended to be caused? If I really wanted some henchmen for my birthday, what would I have to do to get them?