Josh Marshall has a really interesting post on the subject of minority groups and the Republican party. He’s speaking specifically about the black community and their overwhelming support of the Democratic party, but his arguments apply to the relationship between the Republican Party and gay people as well.
Basically the reason why being a gay Republican is not only ridiculous but an exercise in self-defeatism is because the Republican party will never, CAN never, change to be inclusive of gay people, because being anti-gay is part of the definition of being Republican. If the party opened up to include gay people, substantial numbers of anti-gay members would leave the party, and it essentially would no longer be the Republican party.
The Republican Party has not, as Kemp would have it, ignored blacks and other minorities. In the last 30 years the Republican Party has increasingly relied on the support of constituencies that feel embittered and resentful toward minorities and the poor. The party’s mounting strength in the 1970s and 1980s was based on making inroads among conservative southern whites and appealing to the resentments that Democratic northern, working-class ethnic voters felt against school busing and affirmative action. Thus, the GOP’s problem with minorities isn’t incidental; it’s fundamental. Any genuine effort to aid minorities or the poor would instantly alienate a substantial portion of the Republican base. It’s an electoral bind, inexorable and fixed. The Republicans can’t be the party of both black opportunity and anti-black resentment, no matter how big the tent.