Sorry. May sound harsh but expelling them would simply drive the remaining ones underground.
They should just simply disappear.
WE need a big island, and then use like Britain used Australia.
Now your talking! J. Edgar Hoover(back in my day) used to just erase the bastids. Kennedy did away with heads of state for goodness sake! This isn't rocket science.
I thought one way to start would be to listen to the sermons and if they get off color, charge them with sedition. If my preacher can't mention that he's going to vote Republican, then they shouldn't be able to preach overthrow of the gubmint. My preacher just said that he wouldn't vote for anyone that would allow abortion and sodomy, and several people complained that he was suporting the Republican party from the pulpit.I can just see my preacher saying we need to behead people and blow up our children for God! What a load of crap!