I question the validity of the term "Dual-Loyalty". Trying to parasitize or destroy one nation for the benefit of the other indicates that they have only one loyalty.

Not fond of dual citizenship, but there are reasons for it. I'm not sure how many people here would frown at US/Irish citizenship.

Now, congresscritters with dual citizenship, that's an entirely other matter. How can you fulfill your oath or office if you've sworn allegiance to another state?