Semantics....
Obviously it would be insane to try and forcibly change her clothing or become abusive in the situation, however you have the right to dictate your boundaries in a relationship and if the other party isn't comfortable with them you can come to a resolution jointly. The resolution may very well be that you are incompatible and the relationship should end, or that you both give and take and become flexible with your needs and wants.
I wouldn't date a woman that I had to "control", any woman who doesn't care about your boundaries and your comfort level in terms of her attire, relationships with other men, etc doesn't have genuine feelings for you.
Generally this is never a problem. For instance the girlfriend dresses fairly conservatively and doesn't push the envelope, it's just who she is. However if she wore something I wasn't comfortable with I would tell her and she would change. Usually if something is questionable she asks me before she buys it or wears it out.
She can express herself and wear the skimpiest outfits she wants... alone with me. In public, I'd rather she didn't wear anything to short, too low cut, or see through. She respects herself, so I can't think of her ever picking out something I wasn't comfortable with, however we have talked about boundaries in that department.