Cross-dressing is a psychosexual disorder of men who wear women’s clothing for the purposes of becoming sexually aroused. It is a chronic disorder – it cannot be cured, and it will never go away. It is a progressive disease – what starts as masturbating to ads for women’s lingerie progresses to wearing mothers or sisters panties progresses to buying, or stealing, their own lingerie progresses to more complete outfits in tight sweaters, skirts and high heels progresses to wigs, makeup and falsies progresses to sneaking out in public while dressed as a woman progresses to a complete obsession with being seen by others as a sexually attractive woman.
It is a disease. It is men practicing their sexual fetish in public. Exposing innocent women and children, as collateral damage, in their pursuit for greater, more prolonged, sexual arousal. Their desire to publicly practice their sexual
http://www.minddisorders.com/Py-Z/Transvestic-fetishism.html
Transvestic Fetishism progresses to Autogynephilic Transvestism. Autogynephilia creates such an obsession with “being a woman” that men look for excuses to justify their obsession. They become convinced that were actually “supposed to be a woman”. They come to believe they were born with a “woman’s brain”. They claim they are “a woman trapped in a man’s body”.
This isn’t internal, innate identity. Its sexual fetishism. It’s the practice of public sex, with participation forced on others.
Providing arousal. That is why men want to be woman. It provides them with sexual arousal.
OUT of My Panties, Now!!! 
As usual, PoPo, this is exactly what it is. A major fetish, despite how they protest that it isn’t. (“Me thinks the ‘lady’ doth protest too much?”) It is amazing that folks don’t get this unless they are directly impacted by this behavior. Yes, it makes most of us uncomfortable, but we know it is not politically correct to state this. The trans folk have changed the political discourse, twisting it and warping it into how THEY wish to be perceived.