What makes you think that Obama should've immediately posted his long-form birth certificate long ago?
It's only a "red flag" to people who are already overly suspicious. No other president or presidential candidate has ever had to prove their place of birth, why should Obama simply because some people are trolling around for a reason to disqualify him as a legitimate president? I won't even get in to the racial overtones.
What's next? Demand all his college transcripts! If he doesn't release them *immediately* then it is clearly a "red flag" that he didn't actually go to college and that the CIA must be mocking up documents right now. Demand his driver's license! It may be a "red flag" that he actually doesn't know how to drive a car. Demand his vaccination records! If he doesn't it's a "red flag" that he's actually an anti-vaxxer.
It's not OK to demand unreasonable things and then say that since he didn't immediately comply with your demands, it's a "red flag" that your conspiracy theories are true. Additionally, once he *does* comply with your first demand, what's to stop you from making more and more demands until you get the "red flag" that you want?
You can tell the ideals of a nation by its advertisements. -- Norman Douglas