In the book Haldir, I believe, speaks of the power that had returned to Mirkwood. Presumably he is referring to Sauron. But, by the time Frodo was in Lorien Sauron had moved to Mordor. Wouldn't the evil have also moved with him? Or does his evil have residual effects? And I'm not just talking about orcs that may have been left to guard the fort.
"In the midst upon a stony height stands Dol Guldur, where long the hidden Enemy had his dwelling. We fear now that it is inhabited again, and with power sevenfold. A black cloud lies over it of late." Haldir
I think this perhaps refers to the force, or gathering force, that will assail Lorien three times.
Spoken like a true scholar Galin. Glad to see you back, too! It has been way to long for me. I hope to see more of my old friends who are in the scholarly class. Where did you get that idea from? HoME?
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Hey dol! merry dol! ring a dong dillo! Ring a dong! hop along! fal lal the willow! Tom Bom, Jolly Tom, Tom Bombadillo!