https://www.reddit.com/r/PoliticalScience/comments/z8luun/comment/iye158u/?utm_source=share&utm_medium=web2x&context=3
Hi! You’ve stumbled across Constitutional Design Theory!!
So basically there are multiple kinds of constitutions, measured on two axiis; entrenchment and sparity.
An entrenched constitution is a constitution designed to be difficult to change. This is done to preserve and protect certain political principles from being changed by political actors.
A spare constitution is one that is vague in its language. This is designed to allow political actors significant freedom within the bounds of the constitution.
Popular images of what a constitution is depicts an entrenched and spare constitution as the “mold”; the entire point of a constitution is to preserve some very very important things from being changed by the whims of politicians!
And true to that image of the “ideal” constitution, the US Federal constitution is both entrenched and spare. Indeed almost all entrenched constitutions are also spare; a dense and entrenched constitution cannot survive more than a couple generations without failing.
But as Versteeg and Zackin argue (convincingly on this point, less so on others) in the paper linked above, this idea is not born out by reality. Most constitutions are neither entrenched nor spare, and are not intended to preserve political principles at all, but to charter governments.
As you pointed out, Japan and Korea have tax codes in their constitutions, and they’re not alone. Most nations do. Constitutions in these places change often, in some locations as often as every election cycle. They are still different from regular (or statutory) law because the constitution is still considered the document that forms (“constitutes”) the shape of the Government, but they can be changed much more like statutory law.
This is not a non-American thing either; our state constitutions are very much neither spare nor entrenched. In fact, Alabama has the longest and thus (by Varsteeg and Zackin’s measure) the least spare constitution in the world. They have all sorts of things in their constitution, including agriculture subsidies and marriage procedures. Every election cycle, I vote on a new constitutional amendment in my home state of Georgia, most recently to suspend pay for public officials under investigation and to allocate money for disaster relief.
There is an ongoing debate in both academia and the public at large as to which kind of constitution is best, and I try not to include personal opinions in the posts where I’m wearing my teacher hat. Let me know if you want to get into that conversation though!