They haven't asked. For your acceptance, or anybody else's.
Which is why it will take more than a bunch of Corporacrats to bring such a "union" about. I'm willing to bet that if you took a poll of the CEOs of most countries in the Western Hemisphere, the vast majority would favor such an arrangement.
And to add to that point- they actually turned down a clear invitation to join the Early United States.
Article XI of the Articles of Confederation- Canada acceding to this confederation, and adjoining in the measures of the United States, shall be admitted into, and entitled to all the advantages of this Union; but no other colony shall be admitted into the same, unless such admission be agreed to by nine States.
They passed up a golden opportunity.