I made the mistake of clicking on "Remove", and I could not find out how to get the menu back after searching google extensively.
I got the answer by asking the KDE-RedHat forum. Logan Lewis answered the question
> How do I turn the main menu back on?
Right click on the panel. You may have to go into a sub-menu called "Panel menu". Then select "Add Applet to Panel". A window pops up with a description of various applets, you want "K Menu".
It worked for me.
Rick