The USADA don't have the authority to strip the titles from Lance. It would be the UCI along with Tour officials. The whole USADA thing is the fact that they have broken their own rules in persecuting Lance. (ie going back 17 years when their own rules state they can only go back 8, and not actually providing any other body the evidence which they claim to have....)
The whole thing seems to be a witchhunt and it is Lance saying he no longer defends himself against the USADA's alligations.
afaik, USADA do have authority to strip LA of his titles but whether the UCI see that as enforeceable is another matter.
WADA as the world governing body of drug testing has no authority over this, they merely manage the testing (and they are a private body)
USADA as the US drug testing authority have signed an international convention with other country drug testing bodies that basically says that a ruling in one country on a ban for drug testing is enforceable in another. fair enuff.
BUT the UCI has the ultimate control over whether to enforce the bans and whether they can strip him of his titles is uncertain - that may come down to the French authorities.
so what we still have is a potential stand off between USADA and the UCI
I suspect that this will go to the Court of Arbitration in Sport for a judgement.
USAD have broken their own rules in their case against LA; LA has still never tested positive; the evidence against LA is still hearsay and untested in court.
basically the whole thing is still a mess. LA has been smart by doing what he has - he's basically said "I'm still drug free and I've not been able to test my case in court, so over to you fuckers to sort it out. I have a life to lead"