What does 9th circuit or some circuit court mean?
It some name of a specific court, just not the place name?
Or is it special kind of court and “9” is some sort of level? Importance or hierarchy related? Escalation level? (Assuming your SC eventually is also at the top like in India)
Other appeals courts have jurisdiction over other areas of the country - and there is no question of level between them, as they have completely separate jurisdictions.
It's important also that every circuit court is beholden to its own precedent, and every court below them is beholden to the precedent set by their appeals court. But courts in other areas of the country are not - it's perfectly legal (though not extremely common) for one appeals court to decide one way and another to decide a different way on the same matter of Federal law. Unless the SC intervenes, the appeals court of your particular jurisdiction is the ultimate authority on how that federal law is to be interpreted in your jurisdiction.
So, the fact that the 9th circuit decided that Kalshi is a gambling site and not a commodity futures trading platform means that they have to be treated this way by all federal and state agencies in California, Arizona, etc; but they could still be recognized as falling under CFTC rules in Texas or New York, as the 9th circuit decision is not applicable in those jurisdictions.
And I learned an interesting tidbit from one of the commenters here.