I went into my inbox, and performed a search. 2 results came back and I did what I needed to do with those messages. Then, I did not need them anymore, so I selected the checkbox next to the "From / Subject" header, and hit delete and confirmed the deletion.
However, what I didn't realize is that the checkbox was selecting to delete ALL messages in my inbox, and not only the two message that had resulted from the search I performed on the inbox.
This looks like a bug in SmarterMail Enterprise 11.7.