You got me thinking about the relationship of the various elements and that was the path I took.
Seems ul#cssmw > li > a did not have a text alignment value set while the #sidebar alignment was set to center. So the left side of the menu aligned with the center of the sidebar container.
The solution was to left align the #sidebar container and center align the text in ul#cssmw > li > a
Thanks again for the help and prodding.