Why did the Nazgul not succeed in Bree and on Weathertop?

[Durelin]

Originally Posted by Rumil

I've also had the impression that the Nazgul became more powerful the closer they came to Sauron in Mordor. During the passage of the Dead Marshes Sam and Frodo were more terrified by the cries of the Nazgul than they had been in the Shire.

I think this was perhaps only because both Frodo and Sam, and particularly Frodo, had a much greater understanding of what the Nazgul really were. By TTT, Frodo had been carrying the Ring quite a while, feeling its weight, feeling the desire to give in to it... He understood what the wraiths were, and that, essentially, he could become quite like them. I'd say that's enough to cause quite a great deal more fear.

And then there's the simple aspect of being out of one's element - being far far away from home!

Still, you definitely have a good point there. It is perhaps logical that they would be stronger, but that might require more of a mystical connection between the Ringwraiths and Sauron than anyone might be willing to even imagine.