How was the "new" Klu Klux Klan of the 1920s able to fit under the banner of "fundamentalism"?they don't really fit the definition of...

Fundamentalism might not have been the main theme of the
KKK in the 1920s, but it was certainly not that different from what they were
advocating.   During this time, the KKK was promoting what they saw as traditional
American values -- just like the fundamentalists were.

Both
the fundamentalists and the KKK were fighting against the new ways.  Both did not like
the new ideas that were springing up in the cities.  Because of this, it is not wrong to
put the KKK in with the fundamentalists, at least to this
extent.

While it is not right to say that all
fundamentalists were KKK members, they did share some goals
-- they both wanted to return to the values of the past because they did not like the
flappers and immigrants who seemed to dominate the cities.