The ability to have an erection is very important to a man. Without that ability, we cannot fill our sexual role and that's important to us. I would compare losing that ability to a woman losing her breasts (as far as self image issues go).

That said, erections and sexual performance in general are far from being the principal factor in a man's self esteem.

Some of the general pressures faced by men are to be: physically strong, physically/mentally/emotionally resiliant, sexually endowed/powerful/knowledgeable, a good provider/financially solvent, sensitive, emotionally open but simultaneously stoic, mechanically/technically inclined, athletic, attractive, decisive yet flexible, self reliant.

If any of those things are not met, a man is not a man (if you listen to society) and these pressures are very real. So losing your erection, job, looks, muscles, emotional composure, etc. also means losing your masculinity.

And if you doubt that, think of how many women would want to date a man who, for example, didn't have a job.

Cyran0