Well it sounds like your criticism is with the whole system and all its restrictions then - not just the restrictions for certain sexual behaviors. I mean, I have a tattoo, so I can't donate blood. Is it fair to say you think that is equally wrong, or is the thing about gay people more wrong in your view?
Yes, that's true. I am criticizing the whole system. There are other groups, as you point out, that are discriminated against, and I disagree with that, too. I was focusing on gays because of other recent events.
I must say that I'm surprised by the response in this thread. It's pretty simple. they test the blood anyway, and the donors can also be tested before going. It doesn't matter whether one group is higher risk. Other groups are still risky. Numbers I found are 17,465 cases of HIV/AIDS from male-to-male sexual contact in 2006, and 11,584 cases of high-risk heterosexual contact in 2006. Compare them to 4,728 cases of it from injection drug use.
Now, there are a reported 409,982 cases of AIDS in black black people in America since the beginning of the epidemic through 2006 and only 394,024 cases in white people in the same span. So, by the same logic shouldn't they also disallow black people to give blood? If not, why not?
Here's an analogy: If you're out walking and you need to cross the street, does it matter whether it's a small two-lane road that barely has any traffic or a four-lane road with a fair amount of traffic? Either way, you can cross. You just have to be more careful in one case.
The bottom line is that there are better ways to determine whether your blood is acceptable for donation than arbitrary assessments like whether a man has sex with a man, especialy since there are plenty of women who have anal sex with their male partners and yet they don't seem to have a problem with taking their blood.