See novicemama you aren't being precise enough in what you say here;
"what if the Wakefield study was replicated, with ethical approval, with a larger group, with everything done above board? And what if the findings showed no link?"
Which Wakefield study are you referring to? I'm going to guess the 1998 Lancet paper and not one of the 19 other (peer reviewed and published) papers he has written on autistic enterocolitis. This piece of work, which wasn't a study as such, but a report on a case series did not look for a link with MMR, it did not test a link with MMR, it did not find a link with MMR and it did not claim in any way shape or form to have found a link with MMR. It does mention the MMR because it faithfully reports (as is its scientific duty) that the parents had observed that the onset of symptoms coincided with MMR administration. It would have been unscientific to leave this piece of information out and there was no reason why that information should have been left out anyway.
All this report did was document the bowel inflammation in a group of children with similar case histories. It noted that this particular type of inflammation had not been seen before and that it warranted further investigation. Further investigation has been done (in several countries) and the results are the same (in terms of the type of inflammation).
Please try not to patronise others with silly comments about crying conspiracy and default positions when you are asking questions about 'links' that it would be utterly impossible to establish with science which replicated that of the Lancet paper alone. I don't mean to be rude but your question does suggest that you don't know a lot about this - it is a very naive question in terms of the actual science we are talking about.
There are actually a couple of really simple ways to shed some light on this;
One - do a population study comparing vaccinated versus entirely unvaccinated populations. Parents have been campaigning for such a study to no avail for quite some time.
Two - do a primate study. (Actually it is that this hasn't been done to test the increasingly heavy vaccine schedule as a whole. Many of us are very uneasy with the fact that the vaccine schedule is entirely untested). Well that nice Dr Wakefield did a primate study over several years with macaque monkeys being given the standard US vaccine schedule adjusted for size, weight, etc. Apparently the results are concerning - I say apparently because although the paper was accepted by peer review and published online by prestigious journal Neurotoxicology, it has now been censored and they are refusing to go to print with it (even though it was accepted for print initially). The editor of the journal says it was her boss in the publishing company Elesiver who made the decision to censor the paper.
An initial section of the primate study examining the effect of thimerosol containing Hep B vaccination on newborns has been published and AFAIK not censored yet. The results show concerning differences in newborn reflexes and skill acquisition.
Different subject but I'm still interested in your opinion of Professor Walker Smith and the fact that none of the other doctors have provoked the scrutiny of the GMC despite having worked under exactly the same ethical approval as that of Wakefield, Murch and Walker Smith.
The only difference between the doctors who were called up by the GMC and those that weren't is the retraction of the interpretation.