While opinions about America’s post–9/11 policies come and go, facts remain: The U.S. has thwarted 40 terrorist plots through an aggressive and prioritized plan of offense to protect America. That is not a plan to abandon now, in an age of increasingly high-tech terrorism.

As John Yoo, a former official in the U.S. Department of Justice between 2001–2003, said yesterday at The Heritage Foundation, “The most important thing to happen in the U.S. in the last 10 years was nothing… the most important question to ask is why and whether it was worth it.”

Now a legal scholar, Yoo bared his thoughts in a new, multi-authored book of essays on the 9/11 tragedy and its aftermath, Confronting Terror. The book includes reflections from a variety of notable figures on issues like presidential authority during a time of war, enforced interrogation, and other controversial issues.

In the 10 years since al-Qaeda terrorists killed nearly 3,000 American citizens, there has been much anger and some justice—but often, profound disagreement on the best way to combat a new kind of war with a stateless enemy.

Yoo, a co-editor of the book with Dean Reuter, appeared on a panel with contributors former ACLU President Nadine Strossen and Heritage’s Ed Meese.

On 9/11, the future of America’s national security situation was immediately turned upside down. While the nation is unquestionably safer today than it was before 9/11, security questions remain delicate as intelligence experts and military leaders attempt to navigate a safe but effective pathway.

In the book, Yoo criticizes the Obama Administration’s opposition to holding prisoners at Guantanamo Bay, where enhanced interrogation tactics have had led to life-saving information. When American intelligence can no longer obtain that kind of valuable material from the only people who have it, how will the U.S. thwart their plans?

As Yoo writes:

Gaining the information in the heads of terrorist leaders remains the most effective means for stopping terrorist attacks on the U.S. homeland. Our enemy has no territory, population or regular armed forces. It operates covertly, concealing its movements and communications within everyday economic traffic and aims to launch a surprise attack on innocent civilian targets…only by learning al-Qaeda’s plans can we preempt its attacks on the U.S. homeland.

What is known is that the U.S. counterterrorism strategy has worked. To alter a successful tactic for political gain would be foolish. Ten years removes America from the shock of the attacks, but time has offered determined terrorists space to refine plans for another attack.

A big part of keeping attacks at bay is also a strong troop presence overseas. While the President made some good choices to keep troops in place, his strategy has been flawed from the start. Now it’s getting worse, as Congress cuts an already burdened defense budget and faces a heavy troop drawdown—an order that came before the troop buildup even began. Fulfilling political promises to withdraw troops has trumped military security and the necessary incremental assessments President Obama should make as the 2012 election nears.

As Heritage’s James Carafano wrote yesterday on Fox News.com:

The president believes America can be kept safe with a “small footprint” defense—a limited number of special-forces boots, smart missiles and attack drones that can play “whack-a-mole” with a selected number of targets. Covert operations and surgical strikes can be useful tactically, but they are no good as a world-wide strategy.

… Meanwhile, Mr. Obama will peck at them from afar–just as Presidents Clinton and Bush did before 9/11. In a few years we’ll be right back where we were on September 10, 2001.

Yoo echoed these sentiments, noting the success of U.S. intelligence operations in their many forms, including the Patriot Act and enhanced interrogation techniques. He credited the killing of Osama bin Laden as President Obama’s “greatest foreign policy and national security achievement”—recognizing that it came about only through intelligence learned from those detained under the laws of war combined with electronic surveillance to locate bin Laden’s hideout.

As Yoo reminded, most of the post–9/11 national security agenda was approved by a bipartisan majority of Congress again and again. Many who voted for the security provisions now in place have flip-flopped in order to appease a political base.

It’s too easy to revert to pre–9/11 thinking, but America will wish it hadn’t if and when terror strikes again. We are still a nation at war. It’s no accident that 9/11 was the only attack of its kind—lest President Obama and others in Congress begin to think otherwise.

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