I don't really understand this statement. Western values are largely descended from Judeo-Christian values. I don't really see how you get to Christian theocracy by eroding the values that it would impose.
Western values developed largely despite Judeo-Christianity. Christianity is as capable and prone to establishing theocracy as Islam. There is historic precedent, there is support for this in scripture.
Watch this video, as it largely summarizes my reasoning for this as well:https://www.youtube.com/watch?v=Wd6FgYbMffk