That article is lacking in any specific information. It is a bit too broad for me to understand what the author of the article is trying to say.
What I understand is that they are saying: "By accepting the lifestyle of homosexuality, we can not deny the practice of lawful gun ownership and usage." I don't know if this is an argument for accepting homosexuality as a part of our society or if it is a means to say that Guns should be abolished.
I don't know what to say...that may or may not be true. But, I believe being gay is not a choice. It may not be inborn, but it is not a choice amongst the majority of the gay population. Owning a gun is a choice and a right. Perhaps the two share the fact that they may be a right in this country.
There are people from every walk of life, gay or straight, who believe either that guns are bad and evile and should be banished as well as those who believe that guns are just another tool for we humans to use and enjoy.
Personally, I believe this book the article cites is reaching a bit. There are plenty of other reasons to allow both practices besides relating them to one another. Though, it is an interesting take.
There are plenty of gays who believe live and let live, who are conservative and traditional with their morals and values. There are plenty of gays who are leftists. There are plenty of Christians who are gay, there are plenty of Christians who are anti-gun.
