German Chancellor Angela Merkel's outrage over revelations that her mobile phone calls were being monitored by the US National Security Agency leads former senior US intelligence official Paul Pillar to argue that it is not the spying itself that will damage US-German relations, but the fact that these activities are now public:

Even if a foreign government somehow were to learn through its own capabilities of U.S. collection of signals intelligence aimed at its agencies or leaders, its response would be quietly to intensify efforts to bolster its own communications security. To do otherwise and to raise a stink about the matter would risk further compromising its own counterintelligence capabilities and damaging a relationship it would not be in its own interests to damage. It is only when such collection activity is made public through a leaker, with all of the embarrassment and public pressures that are triggered by such a revelation, that leaders feel obliged to take conspicuous umbrage, with all of the further damage that entails.

This seems exactly right to me, though it leads Pillar to a curious conclusion: the US government should not buckle to pressure from leakers and their collaborators in the media. Instead, it should redouble efforts to prevent similar damage in the future. Writing in Foreign Policy, David Rothkopf list a few reasons why this might not be the best approach.

First, it assumes that future Mannings and Snowdens can be stopped. 'But', says Rothkopf, 'even the most perfunctory risk analysis has to conclude that in any system where 500,000 people have top-secret clearance, some secrets will not be kept.'

Second, Pillar's argument contains a status quo bias. He assumes that the current scope and scale of America's intelligence collection activity is about right. But given the impossibility of stopping all leaks, the WikiLeaks and Snowden revelations ought to lead to questions about whether the balance between effort and reward has changed. Or, as Rothkopf frames it, 'Is the intelligence we might be gathering worth the risks entailed by getting it?':

Yes, many governments spy. But so too do all countries have armies, police forces, and tax codes. In each instance, the question is not whether to pursue the activity -- it is how to do it, how to limit it, and what values should underpin it. Our spying has overreached. We took risks we shouldn't have for rewards that were too limited. Even when there were perceived threats that seemed to warrant these activities (and that cannot be the case in some of the recent examples we have encountered of spying against friends and companies), many of those threats may themselves not have been so great to warrant the risks associated with spying. What if the NSA scandals result in a more fragmented global Internet? What if they are used as an excuse by repressive regimes to violate their own citizens' privacy? What if they are used as an excuse to deny U.S. companies access to their markets? What if they are used as an excuse to justify similar actions against the United States?

None of this to excuse the actions of Manning and Snowden. It is merely to acknowledge the facts: there will always be leakers, and as the number of people with clearances grows, as the amount of intelligence collected grows, and as the means to swipe huge amounts of data quickly and inconspicuously grows, governments will have to rethink some of their assumptions about the benefits of classified intelligence.