Well it already makes decisions that it "thinks" are good for itself. Those may not always be correct in the grand scheme of things.

But - suppose peoples minds were given a means to connect (and lets leave the science out of that for now). Lets theorize for simplicity that they all hash out their opinions, some opinions bully their way into the lead, and a collective consciousness actually forms without driving everyone crazy since they can't get away from each other and have a little privacy in their minds.

Now double back to anything you know about how the human brain works, how neural pathways grow, combine that with anything you know about AI and artificial learning neural networks. On top of that - (I've witnessed this personally) note that after a serious brain injury someone's personality can change quite drastically. The neural pathways that formed in their lifetime have been severed due to brain damage. New pathways are formed after the person emerges from their coma and goes back to their normal life. But the person is strangely different than they were before.

So... if you can have that much change within the neural pathways of one human brain it's insane to theorize what the behavior would be if all those brains were able to communicate in one large network.

However a mass American brain is trained for self indulgence and commercialism. It's doubtful a sudden cohesion of intellectualism would change that.

On the other hand - if you step back from life and try to zoom out your lens a bit you could already picture each country as their own organism with cells (humans) running around keeping things running. To someone with a big enough view each country probably already looks like a single consciousness. Most people just aren't generally aware of it as such - perhaps the leaders are.
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