There are some dangerously false assumptions in Nuland’s simple sentence.
She is assuming that radical movements are saying things to please voters in the same way that American politicians do. But American politicians are overwhelmingly unideological. Deep down, few of them think that ideas matter. But what if they sincerely and passionately believed that every plank on their platform was ordered by the supreme being and that this was in fact the only reason their political party existed?
Suppose their rivals were willing and able to destroy their careers or even kill them if they showed they were totally phony in their devotion?
Suppose a large portion of the masses took all of this seriously and meant to hold them to their promises? And suppose they truly believed themselves that instituting Shari’a law – perhaps at most with a slightly more liberal interpretation here and a few exceptions there – was the only way to govern?
In other words, there are lots of reasons for radicals to remain radicals in government. And, after all, that is what usually happens.