Indeed, mutually assured destruction was the motivating force for nation states to Not Go There with nukes. Here, however, the motivation for governments to eschew mass surveillance must come from a vocal populace and web-business interests.

If "we the people" don't speak out against this, both on a grassroots and lobbying level, there is no motivation for our governments to abstain. States love to spy on one another; it gives justification for their budgets. Only individual citizens, businesses, and other free thinking organizations have anything to lose.