No president has ever become gay, because it is impossible to become gay. Sexual orientation is something you're born with.
There is no legal reason why a gay can not be president.
Yes, gay people are allowed to run for president.
People don't decide to become gay, they're born like that.
Nobody becomes gay. People are either born gay or they are not.
Yes, but only gay women. Gay men cannot.
No, most people don't want to be gay. People who are gay are either happy, or not, with the way they are. People who are straight do not want to become gay. Anyway, it is not possible to seriously change from one to the other. Nobody can become gay, everyone is born knowing they are gay. Some people are too afraid to come out and accept that they're attracted to their gender, so those who "become gay" have always been gay, they just came out a little later than they should have.
Gay people do not "become" gay. Sexual orientation is fixed at a very early age, possibly birth or prenatally. There have been gay people since the dawn of humanity.
You're thinking of transgender people, not gay people. Gay people do not "become a girl" unless they are also transgender. Transgender people can be gay, straight, or anything else.For more information about the hormones that Transgender women take, click here.
President Obama supports full equality of gay people, including military service.
No, in fact he supports murdering gay people for being gay.
All people, gay or straight, adapt to their environments. But if you are asking if a gay person can become straight, the answer is no. It's not possible.