You're exactly right. Monopoly got us so far. Competition is now getting us to a whole different stage. But to get to competition from what was a monopoly, there's a need for good regulation, as the government displayed with the wireless auction process. That was good regulation to get to more competition.
In this case, the foreign investment restrictions currently affect those who would compete more than they affect those who are, as you say, already in the market with their networks deployed.
Just one point on my friend's comments: wireless calls don't fly from one phone to the other through the air. They find a network, and then they go along that network. Our network is one of the largest backhaul providers to some of those new entrants. So the network will always be important, and finding people, new and existing, who will invest in that network is really crucial, and that's why the investment restrictions are a direct limiter on that.