06/11/2013 02:20 pm ET Updated Aug 11, 2013

NSA Surveillance

The revelations that the U.S. government has been collecting phone and Internet data has reopened a debate about the balance between privacy and security, at a time when America is becoming an increasing target of terrorists.

Last week, President Barack Obama defended the government's surveillance programs, "You can't have 100 percent security and also have 100 percent privacy and zero inconvenience." He continued, "We're going to have to make some choices as a society. On balance we have established a process and a procedure that the American people should be comfortable about."

The Fourth Amendment of the United States Constitution guards American citizens against unreasonable searches and seizures, unless authorities get a judge to approve a warrant based on probable cause. But does this extend to the mass collection of phone numbers and the duration of telephone calls?

Senators Mark Udall and Ron Wyden, members of the U.S. Senate Select Committee on Intelligence, have called for more public disclosure about how the telephone surveillance program is run. "Now that the fact of bulk collection has been declassified, we believe that more information about the scale of the collection, and specifically whether it involves the records of 'millions of Americans' should be declassified as well," Wyden and Udall said in a statement issued Friday. "The American people must be given the opportunity to evaluate the facts about this program and its broad scope for themselves, so that this debate can begin in earnest."

Does the Fourth Amendment extend to Internet metadata, which is data about data? Metadata can be structural, data about the design of a webpage, or descriptive, data about the content and links. IBM estimates that 90 percent of the data in the world today was created in the past two years. Each day, according to IBM, 2.5 quintillion bytes of data are created, including from social media, email, digital pictures and video uploads, cell phone GPS signals, and blogs. We live in the Big Data era.

Gen. Michael Hayden, a former director of the National Security Agency (NSA), told NPR's Weekend Edition Sunday that the programs are lawful and justified in the war on terrorism. He stressed that the Internet surveillance program, known as PRISM, is "about Internet data, not telephony, and it's all about foreigners." He further explained, "So, if I've got a bad person in Waziristan, talking to a bad person in Yemen, via a chat room that is hosted by an American Internet service provider, the only thing American about that conversation is the fact that it's happening on a server on the West Coast of the United States."

Revelations that the NSA collects data on phone conversations are not new. USA Today reported its existence in 2006, saying, "This program does not involve the NSA listening to or recording conversations. But the spy agency is using the data to analyze calling patterns in an effort to detect terrorist activity, sources said in separate interviews."

A recent Washington Post-Pew Research poll found that 62 percent of Americans sampled favored investigating threats even if it intrudes on privacy, while 34 percent responded that the government should not intrude even if it limits the ability to investigate threats. But this presumes that the government has all the right procedures in place to limit the scope of its investigations to threats of terrorism. In other words, Americans must trust the government to do the right thing.

In his remarks last week, President Obama said he welcomed the debate, noting, "If people don't trust the executive branch, and also congress and the judicial branch, then we're going to have some problems here." But this is a complicated issue, and there are plenty of examples in history when the government has exceeded its authority.

The government should fully disclose to the American people the procedures and safeguards built into these programs against unreasonable intrusions into their constitutional rights of privacy.