I took the advice of a user to edit titles that have misspelled or duplicate keywords when there are a few titles to edit. However, this doesn't seem to get rid of the keyword. For example, the keyword "walter-reed-hospital" was used once and I changed it to the more frequently used "walter-reed-army-medical-center". However, the keyword "walter-reed-hospital" has not gone away though it now shows 0 titles using it. Will they eventually go away?

Now on to keywords that should probably be merged. These all refer to the same thing:
u.s.-mexico-border
u.s.-mexican-border
us-mexican-border
mexican-american-border
mexican-border should probably be merged into this group as well, though it is non-specific (Mexico only has two borders and this being a US based site, it probably means the US/Mexico border and not the Mexico/Guatemala border which also has a keyword.)
Also, these are the same:
texas-mexico-border
mexico-texas-border

Now on to keywords that should probably be merged. These all refer to the same thing:
u.s.-mexico-border
u.s.-mexican-border
us-mexican-border
mexican-american-border
mexican-border should probably be merged into this group as well, though it is non-specific (Mexico only has two borders and this being a US based site, it probably means the US/Mexico border and not the Mexico/Guatemala border which also has a keyword.)
Also, these are the same:
texas-mexico-border
mexico-texas-border



Adrian, Champion
Adrian, Champion