As the 2nd of 4 generations of Boy Scouts (my own Eagle- and Scoutmaster-father, my Eagle-Scout Uncles, various Star-, Life- and Eagle-scout cousins and myself, Eagle-scout nephews, and First-cousin-once-removed-Scouts, etc) (but not my grandfather, born in 1898 who theoretically could have been a Scout, if he had been born in England and not in a small, Nevada mining town), I have a few thoughts:
One of Scouting's greatest gifts was that people who weren't otherwise included (for reasons of economics, race, or non-Christian religion) could rub shoulders with some of the upper crust*, learn some skills, and be judged for their character rather than their origins.
*Portions of each of those four generations lived in Piedmont, California. Which is both more elitist on economic grounds but more inclusive on other grounds. Their "Council" - a single troop council - doesn't discriminate on the basis on race, ethnicity, sexual orientation, or home address.
35 years ago, I remember thinking of BSA as being inclusive - you could be almost any flavor of Christian, Jew, or Muslim, as long you believed in one(!), male (!), singular (!) God. 35 years later, more aware of the variety of people in the world, I don't think of them as inclusive. I'm no longer 15 years old and I'm no longer such a product of a middle-class, suburban bedroom community. So I now see unfortunate limits to BSA's concept of the world/universe/morality.
It saddens me that BSA can't see that some of the practices that made them noble - seeing beyond racial and religious persecution - can't still be part of their mandate. Just look at GSA - inclusive not just of race, class, and orientation but of gender itself.
To be blunt - BSA has two great hurdles. (1) pedophiles are almost all male. Sorry, guys, it's true. Men are, overwhelmingly, the butt/mouth/t-w-a-t F'ers on the planet (among bipeds). And (2) the LDS church is both incredibly homophobic AND 1/3 of Scouting. They've made it clear to BSA (reference, Time magazine, circa 2010) that if BSA is more inclusive, LDS walks away and the organization (the fear goes) implodes. Should you trust your sons to a group who (when they knock on your doorstep) deny that until 1978, the "son of Cain" was unworthy of priesthood in their church?!? Let me go on record as proclaiming that the only kid in my high school who was smarter than I was, was a "son of a Cain" - a dark-skinned black boy who ALWAYS knew more math, science, and current events than I did. So, yes, I call foul on the Mormon Church's claim that Howard (now a university math professor) wasn't as least as human as I was in 1978.
So we've got a group that could be a tremendous force for positive morals, ethics, and self-sufficiency becoming a regressive organization all because of a Utah-based religion founded by someone convicted of bank fraud and because of a closeted g.a.y guy in Rome who wears red shoes and pointy hat. What are WE to do? We, who see the value of being in the outdoors, learning skills, and leadership? I've told an MD in town - the Mormon on the School Board* - that I can't support his campaign for higher office because I've seen him vote against protecting g.a.y students and staff from discriminatory practices.
*Call out to Nels Anderson, MD, Soldotna, Alaska - I don't think you should be able to escape a Google search for imposing your bigotry on the very students I think you should protect.
Back to the original question: Do you fight from within or from outside?
Is BSA like Nazi Germany and anything is worth the price of their downfall? No, it is not that bad.
Is BSA like your neighbor, the tax evader, who only damages the USA a few thousand dollars? No, it is more than that.
Personally, I try to use both a stick and a carrot. I call them out for their bigotry, even if some locals think that defending the "f.a.g.s" isn't as noble as defending Christians, Jews, Republicans, and Y2Kers. I (and my far richer wife) donate a ton of money to more progressive organizations. Oh, look, BSA - people who've gone to college, met different kinds of people, learned a profession, and gotten a state license - we would support you like other forces for good, if only you were more consistently a force for good.
Does BSA have a "right" to discriminate? Yeah, sure. In the USA. Germany, at least, doesn't give their resident Nazis a pass.
Is it a wise political or financial decision? I aim to make it not a good choice. Again - bluntly - those of us who have been to college, met (and loved) a variety of people, and earned a bunch of money - we get to have more influence. And I vote for inclusion and moving forward. For a more inclusive society, a less fearful society. How does your "right" to marry ONLY an opposite-gendered partner trump their right to keep their job if someone discovers they love someone with similar genitals?
Your fears don't negate someone else's Civil Rights. They shouldn't have in 1863 and they shouldn't in 2013!
The more miles I hike through the forest and along the rivers, the clearer this becomes.