Gen. Keith Alexander, the head of the National Security Agency, believes the threat of terrorism is so great that his agency can invade the traditional American personal right to privacy.

U.S. Rep. James Sensenbrenner, a Wisconsin Republican and one of the authors of the USA Patriot Act — used by Gen. Alexander as the basis for his agency’s actions — believes the NSA goes well beyond what Congress intended in reacting to the 9/11 attacks.

Between them, they reflect an historic battle over the role of government in protecting Americans and the rights of Americans to be protected from a powerful government.

The Patriot Act was an almost reflex reaction to the al Qaeda attacks in 2001. Congress gave the government unprecedented intelligence capacity, trying to make sure that terrorist attacks could be thwarted before they took place.

In the face of an external threat, the United States has a history of taking drastic action to show a sense of national resolve.

After Japan attacked American forces at Pearl Harbor, American citizens of Japanese origin were thrown into prison camps and their property was seized.

When the Soviet Union loomed as a dangerous rival for world power, American planners credited them with a vast military capability that required an even greater response in U.S. military spending. Other public goals were sacrificed to support that spending.

Eventually, some Japanese- Americans were freed and provided heroic military service in World War II.

And when the Soviet Union collapsed, Americans learned that we had greatly overrated its military capability.

Are we now sacrificing the rights of Americans, because we overrate the terrorist threat?

We may be, according to a recent article in Scientific American magazine. The report summarizes several studies discussing the “myths” attached to our understanding of terrorism.

First, it reported that, despite fears of terrorism’s goal being the spread of “radical Islam,” Islamic extremists are motivated not by ideology but by their belief that the U.S. has targeted Muslims, or by revenge for American support of Israel and intervention in Iraq and Afghanistan.

Terrorism is not a “vast global network.” Instead, it is decentralized and based on social networks. In other words, it’s more about family and friends than some central mastermind.

And terrorists are not clever planners. After the top leaders are gone, they have shown themselves to be “incompetent fools.”

Terrorism is a lot less deadly that might be thought. Since 9/11, there have been about 13,700 homicides a year in the United States — with 33 deaths since then caused by terrorists.

Finally, terrorism doesn’t work. Terrorists have failed to achieve their goals. Their groups last an average of eight years and their leaders generally don’t survive.

Of course, these conclusions do not relieve the government of the responsibility to deter and prevent terrorists. But they suggest that the threat might be met without broad incursions on the privacy rights of Americans.

After 9/11, almost no member of Congress wanted to appear “weak” in responding to the terrorist threat. That sentiment produced the Patriot Act.

As tough as that law has been in limiting traditional civil liberties, government agencies have interpreted it to be even tougher. And the sole control has been the secret Foreign Intelligence Surveillance Act Court.

In that court, everybody from Google to the average citizen could be put under surveillance without even knowing about the proceeding or being able to argue against invasion of their privacy.

In other words, the post 9/11 mechanism of the federal government has said that, in order to protect Americans from terrorists, it would have to reduce individual rights — the very values at the heart of the country. And that trade-off has been made without a vote by representatives of the people.

Now, Sensenbrenner and Democratic Sen. Patrick Leahy of Vermont have written a bill called the USA Freedom Act, designed to somewhat rein in the NSA.

The bill would prevent the sweeping collection of data on American citizens and would create a Special Advocate to defend the “civil liberties” of those to be placed under surveillance. It would require more public information about the activities of the FISA Court.

Interestingly, the bill has the support of groups, ranging from the National Rifle Association to the American Civil Liberties Union.

Among the first 88 U.S. House and 16 Senate members sponsoring the bill is U.S. Rep. Mike Michaud. Many members of both parties — liberals and conservatives— have signed on, rare in this era of political polarization.

Sponsors take the position that if counterterrorism is meant to protect American freedom, it must also respect it.

GORDON L. WEIL, of Harpswell, is an author, publisher, consultant and former public official.

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