Some of you may be wondering whether I'm on the right side of this debate. I've devoted my life to protecting privacy and civil liberties, yet I'm for this proposition. I am because I sincerely believe that surveillance properly conducted and properly limited can really and genuinely protect our liberties. Look, no state has ever survived without some surveillance, and no state deserves to survive if it has too much surveillance, particularly against its own citizens. A balance has to be struck, but that balance cannot eliminate the power of government to obtain information necessary to the defense of our freedoms.

A proper balance requires a proper process for deciding when surveillance is justified. When the need for preventive intelligence is greater in any particular case than the need for privacy. And in striking that balance it's important to distinguish among different types and degrees of surveillance. There's a considerable difference, for example, between street cameras that observe the external movements of people in public places and hidden microphones that can listen to what you're saying in your bedroom. There's a difference as well in accessing the content of phone calls and emails and in cataloging the externalities of such messages—to whom they're sent, when they were sent. There's also a considerable difference between surveilling our own citizens and surveilling foreigners including foreign leaders, who are probably trying to listen in on our leaders conversations. To fail to base our policies on this difference is to fail in the very act of governance, which requires nuance and calibration.

Matters of degree matter. And differences in degree can differentiate pragmatic democracies who are genuinely seeking to protect their citizens against real harms from self-serving tyrannies that seek only to protect their leaders from accountability.

We will hear tonight that terrorism and the need to protect our citizens is only a pretext, that there are other motives, sinister motives, for why we'd collect this information.

So I will throw out a challenge out to our distinguished opponents.

What are those motives? Why would the Obama Administration continue this policy of surveillance after being briefed? Was it because President Obama has some sinister motive that he won't tell anybody about for gathering this information and is only using terrorism as a pretext the way the Nazis in Germany used the Reichstag fire as a way of suppressing civil liberties? I don't believe that.

I hope you won't either.

Motives matter, though they too are difficult to discern and are frequently mixed. Many who supported the surveillance conducted by the FBI against the Ku Klux Klan and other racist groups during the civil-rights movement opposed the very same surveillance techniques when they were used years later against the Black Panthers. And many who now applaud the decision to publish the illegally recorded private statements made by Donald Sterling to his mistress would express outrage if equally pernicious statements made in private by people they admire and respect were subject to public disclosure. Privacy for me but not for thee is as common as it is cynically self-serving. Now we ought to be concerned about surveillance. There's virtually nothing that's immune from the pervasive eyes, ears and even noses of the new generation of Big Brothers. It's absolutely true. But the most dangerous approach to our liberties is the all or nothing one proposed by radical proponents and opponents of all government surveillance. Those who oppose all surveillance are as dangerous to our liberties as those who uncritically support all surveillance.

We need to know what harms our enemies, external and internal, are planning in order to prevent them from carrying them out. We also need to impose constraints. And that's why process comes into play. We need a demanding process. But we need to make sure that the burden is realistically designed to strike a proper balance between two equally legitimate but competing values, the need for intelligence to stop attacks against us and the need to protect our privacy from those who place too high a value on security and too low a value on privacy.

I believe it is possible to strike that balance in a manner that protects our freedoms, and that is where our efforts should be directed. Surveillance properly limited and appropriately conducted can promote liberty, protect life, and help us defend our freedoms.

Our enemies, especially those who target civilians, have one major advantage over us. They are not constrained by morality or legality. We have an advantage over them. In addition to operating under the rule of law, we have developed through hard work and extensive research technological tools that allow us to monitor and prevent their unlawful and lethal actions.

Such technological tools helped us break the German and the Japanese code during the Second World War. They helped us defeat fascism. They helped us in the Cold War. And they are helping us now in the hot war against terrorists who would bomb this theater if they had the capacity to do so. You're going to hear again that there are only excuses that are being offered, that terrorism is really not a serious problem, or that American policy is as terroristic as the policy of al-Qaeda. I don't think you're going to accept that argument.

We must not surrender our technological advantage. Instead we must constrain it within the rule of law by constructing appropriate processes governing its use. I urge you to vote against rejecting all state surveillance properly regulated as a legitimate defense of our freedoms.

I urge you to vote yes.