What?! How do you see that? The ", and" below is a conjunction, it's joining one commitment and another into a list of commitments made to the States:
| The United States shall guarantee to every State in this Union a Republican Form of Government, and shall protect each of them against Invasion; ...
That clearly does not predicate one commitment upon the other. It's just a list of commitments.
The key word in my comment is "additional", which was intended to indicate that I was replying to "and shall protect each of them against Invasion".
I have to admit it's also partially my fault since I didn't notice at the time that you are not the same person who made the original comment I replied to, so I left out some context.
Otherwise I agree that it is just a list of commitments.
> The Republican Guarantee is a commitment of the Federal Government to the States about the States.
I'm not quite sure where the "about the states" part came from. To me, Article IV just reads like a set of promises the federal government must make to the states.