It didn't take long to find the workaround--thanks to Nilesh Kapadia who commented at http://emacs-fu.blogspot.com/2009/07/emacs-23-is-very-near.html.
Insert the following into the .emacs startup file:
(setq line-move-visual nil)
This seems to be yet another case of someone wanting emacs to act less like a text editor and more like a word processor. People that want emacs to act like a word processor should use a word processor, and not lobby to cripple emacs' ability to treat text like text.