2013/9/5 Rob Pike <robpike@gmail.com>
Try

set +o emacs

(sic)

Thank you, that did it.  Interesting that it's a +o command
to turn something off.

bash(1)
...
READLINE
       This  is  the library that handles reading input when using
       an interactive shell, unless the --noediting option is given
       at shell invocation.  By default, the line editing commands
       are similar to those of emacs.  A vi-style line editing
       interface is also available.  To turn off line editing after
       the shell  is  running, use the +o emacs or +o vi options
       to the set builtin (see SHELL BUILTIN COMMANDS below).
...