Great points, thank you, but I think I still disagree.
In the absence of the 2A, the government would have the power to ban any weapon (using the same authority they have to ban weapons that are not covered by the 2A today). By contrast, under your proposed fictional constitution, there would be no underlying basis for the government to control clothing generally, so your 2A wouldn't expand or limit the sorts of clothing allowable.
As for your second point, I interpret the "justification clause" as saying that all retrospective laws are ...unjust, and that "No such laws" means "No retrospective laws". The hypothetical of a ...just ex-post facto law is ruled out by definition.
In the absence of the 2A, the government would have the power to ban any weapon (using the same authority they have to ban weapons that are not covered by the 2A today). By contrast, under your proposed fictional constitution, there would be no underlying basis for the government to control clothing generally, so your 2A wouldn't expand or limit the sorts of clothing allowable.
As for your second point, I interpret the "justification clause" as saying that all retrospective laws are ...unjust, and that "No such laws" means "No retrospective laws". The hypothetical of a ...just ex-post facto law is ruled out by definition.