It is not often that the phrase "must-read article" is seen in this space, but The Atlantic's Derek Khanna has provided an entirely suitable occasion for that appeal. Khanna's article -- entitled "If PRISM is good policy, why stop with terrorism" -- is indeed worth reading by every American concerned about how this nation conducts the war on terrorism. Virginia's James Madison -- fourth president of the United States, chief intellectual architect behind the U.S. Constitution, and co-author with New York's Alexander Hamilton of the Federalist Papers -- would second Khanna's fundamental point. And not only because Madison presciently spoke these words to the Virginia Ratifying Convention: "There are more instances of the abridgment of the freedom of the people by gradual and silent encroachments of those in power than by violent and sudden usurpations."

Khanna prominently notes Madison's warning in the Atlantic in making his case that the National Security Agency's Prism surveillance program represents what the Virginian had in mind. Created in response to 9/11, Prism monitors billions of daily emails and cellphone calls produced by millions of Americans with no known connection to al Qaeda or any other terrorist group. The program also monitors the locations of these same Americans, whom they contact, how long they talk, and credit card transactions. The government, including President Obama, claims only the most minimal data is collected -- just enough to detect suspicious activity -- but all that is required to breach that firewall is the consent of a secret federal court.

Terrorism is an insidious foe because its combatants don't wear conventional military uniforms and don't operate according to the rules of traditional warfare. Sometimes they come from overseas, other times they are recruited from among the American citizenry. They almost always operate surreptitiously and strike against innocent men, women and children with the goal of inflicting mass casualties. Identifying, locating and defeating such an enemy is an almost impossible task. As Khanna puts it, "terrorism is by definition designed to 'shock and awe.' It is theatre of the macabre."

But does this reality mean the government must be able to track and collect massive amounts of data about virtually every adult American that would otherwise be private? Or to put it another way, everybody agrees that the federal government's most basic responsibility to defend America against all enemies, foreign and domestic, but where should the line be drawn between that necessity and the enjoyment of constitutionally protected individual rights?

Khanna asks a crucial question: "But if we are going to use personal data obtained through PRISM for terrorism purposes in a way that violates our privacy and which I would argue violates the Fourth Amendment, why not do it for other legitimate purposes?" Among such purposes, Khanna points to combating child pornography, policing speeds on highways and protecting copyrights. Additional worthy causes could easily be added to the list, such as fighting drug cartels or exposing serial killers. Or to put it yet another way, are Americans ready to let politicians define individual rights instead of the plain words of the Constitution?