If this kind of attacking does escalate, wouldn't it be possible to simply cut off requests from outside the United States at the points of entry? Basically, turning the US into an intranet?
We don't know yet, but the attack very easily could have been coming from a botnet of devices entirely inside the US. Geographic borders don't matter much at all for the Internet.
But even if it were, the creator of the botnet would first have to gain control and then issue a command, right? How would either of those things be possible from outside if there was no connection into the US?
Well, there's pretty much no way to impose the geographic borders of the US onto the Internet. Our networks here in the US are all global and integrated with other networks all around the world. The only places where this kind of geographic control is possible are countries like Iraq, Iran, China and others where the government controls all the ISPs. Countries with more freedom have a free flow of information and packets - and to me that is a very GOOD thing.
If this kind of attacking does escalate, wouldn't it be possible to simply cut off requests from outside the United States at the points of entry? Basically, turning the US into an intranet?