Do you think short hair in men is considered being under society's control, such as in military or prison?
No, it is more for their comfort.
I think so too. When it comes to hair style comfort is the priority in my opinion. They should not feel uncomfortable
Some men like long hair for beauty reasons and some like short for same reason.
I agree. Aside from beauty it can also be many other reasons such as fashion, culture, and trends
Men look good either way with both long and short hair.
I have long hair which reaches my chin.
Very nice.
Long hair
Long hair is a hairstyle where the head hair is allowed to grow to a considerable length. Exactly what constitutes long hair can change from culture to culture, or even within cultures. For example, a woman with chin-length hair in some cultures may be said to have short hair, while a man with the same length of hair in some of the same cultures would be said to have long hair.
Males having short, cut hair are in many cultures viewed as being under society's control
considered a mental disorder or the hallmark of one; it is sometimes used as a synonym for lateral thinking. 
Examples.
- "The next day when I'd be going out you know, I took control, like uh, I put bleach on my hair in California."—given by Nancy C. Andreasen
- "I think someone's infiltrated my copies of the cases. We've got to case the joint. I don't believe in joints, but they do hold your body together."—given by Elyn