Hello, Rich.

Thank you for contacting us.  Actually, Smarky does have a Tags View, but it is collapsed by default.  Hover your mouse over the left edge of the window and the cursor will turn to a vertical bar and right-pointing arrow.

In Smarky, we chose to collapse the Tags View by default because Safari does not display the tags.  Your tags will be preserved through Safari imports and exports, and you will see them and be able to search by tag etc. in Smarky.  But Safari does not show tags, so we figured that most users would not be pleased with this experience.

For this reason, you may prefer to use Markster.  Unlike Smarky, Markster is designed to be left running all of the time.  When you want to visit a bookmark, you switch to Markster using a keyboard shortcut or menu extra.  When you use Markster, you do not use the built-in bookmarks in Safari.  To reduce confusion, I recommend deleting all of them, so that you have an empty Favorites bar and empty Bookmarks Menu, and clicking View > Hide Favorites Bar.

The disadvantage of Markster is that, if you have Safari on an iOS device, your bookmarks will not sync to Safari on the iOS device, because iCloud syncs the Safari built-in bookmarks.

If you decide that you want to switch from Smarky to Markster, you can switch the data you have created, including tags, like this:

• In Smarky, hold down the command ⌘ key and click the window title, Smarky.bkmslf.  A contextual menu will appear.
• Click the first folder in the menu, BookMacster.  A Finder window will be open and Smarky.bkmslf will be selected.
• Quit Smarky.
• In that Finder window, rename, or copy if you prefer, the file Smarky.bkmslf to Markster.bkmslf.  If you've already run Markster, you'll need to trash or rename the existing Markster.bkmslf file first.
• Launch Markster and you should see all of your stuff that was in Smarky.

P.S.  I blame Apple for the hidden Tags View in Smarky.  If you would run Smarky in an old version of OS X, you'd see a little dimple control along the left edge of that window.  But, for the last few years, the designers at Apple have been on a vendetta to make the OS X user interface "flat and clean".  Controls have been shrinking, hiding, reduced to cryptic icons, drawn with so little contrast in the colors that you cannot read them without a Retina display, or disappearing altogether.  It's a fad.  I'm hoping that maybe their pendulum will start swinging back to making things more discoverable soon.