Shalamabobbi: Thanks for the link to this thread.
It is not possible to "convince" a Creationist. It is a basic philosophical difference whose gap is so deep it cannot be bridged. Simply put, a Creationist's view of life in this universe is firmly planted on the simple "I believe" (in this case the inerrant word of God as written in Genesis). The only way to shake that is to destroy that belief. I don't know if that destruction is either wise or in most cases, doable.
A scientist (atheist or a theist who accepts science, and yes, this does imply that Creationists are not only anti-Evolution, but anti-science, in general) accepts only the statement, "show me and prove it through the scientific method". These worlds cannot be reconciled.
The solution is to take, say Mississippi and Louisiana (so a lot won't have to move), toss all the Creationists in there. Call it Creoland. But, make sure they get none of the benefits from science, i.e. let them wallow in what the say they want. And let them take the consequences of their belief. The USA can be the rest of the country. Borders will remain open for immigration both ways, but no Creationist evangelism will be allowed in the USA and no teaching or bringing the benefits of science will be allowed in Creoland.
It's vicious. It's impractical. Humans seem bent on saving others from their errors. But it's the only way I can see to deal with Creationists that will work, at least theoretically.
(as an aside, this could also apply to other deep philosophical divides, like Marxism and Capitalism - i.e. let them live with what they espouse and get benefits from nowhere else. Lincoln (IIRC) said something like "you've made your bed, now lie in it".