How do I use Git's `difftool` to merge conflicts?

After a merge failed with some conflicts, I can list those with git diff, but git difftool won't display them with the difftool set in the config (in my case Kaleidoscope). Instead it will just use normal diff.

A git difftool comparing with a previous commit will work.

Is there a way to use git difftool on merge conflicts?

Try git mergetool.