Great! So we should promote smoking along with homosexuality in public schools. The dangers are roughly the same (depending on which study you want to bring up). We should have "Be tolerant of smokers days." "My Daddy smokes like a chimney and drinks like a fish (and it's cool) day." Kids write letters to congress telling them that chain smokers should be allowed to adopt, etc.
You are correct that homosexuality has not been proven to be genetic. However, there is evidence that genetics plays a role.
And the same can be said for crime. Should we promote crime due to this? The same logic is being applied in order to promote homosexuality. He/she can't help it - they were born that way."
You jest, "My Daddy smokes like a chimney .. and it's cool." I should mention: My own father died of lung cancer late last year. He was a former heavy smoker. These dangers are not abstract or theoretical. There are 120,000 lung cancer deaths a year attributable to smoking; this is several times the annual death toll from AIDS. (I should also mention that I have lost a good friend to AIDS, about a dozen years ago.)
There is a difference between homosexuality and crime. Other than the obvious one that homosexuality is no longer a crime in this country, it is possible to be a homosexual and harm no other person. Indeed many homosexuals are highly productive members of society (professors, engineers, lawyers, etc.). This realization is one of the reasons why homosexuality was taken off the list of mental illnesses three decades ago.