First of all, LD is always global not specifically america unless specified.
True, I don't really mind that.
Secondly, The constitution is often wrong, i.e. slavery.
I would differ on the idea that it is often
wrong-one or two things are objectionable (income tax for me). But the Constitution was founded upon core and largely-unchangeable principles that still hold true today. Most judges would have this in the back of their mind.
And thirdly, who cares what the constitution says, the question is which is more valuable not which is currently american policy.
I care what the constitution says because it makes sense. And what you say is true, you can definitely make it an LD subject, but that doesn't mean it isn't one-sided.
Don't get me wrong, I'd support putting this up for a vote to the NCFCA community, and I think it could produce some valuable debates (I would want every homeschooler to know why exactly a global government is a bad idea). But I think it would quickly exhaust its profitability. I can say that when I'm a judge next year it would be hard to eliminate my bias on the subject. So I can't answer "yes" to your poll question, though I think it covers an important subject.