The 10th anniversary of 9/11 provides a prime opportunity for taking stock of the war that began a day later.
To begin, this really is a war.
The Bush administration used the term "global war on terrorism" to give form and focus to post-9/11 military operations. Effectively validating the term, the 9/11 Commission concluded in 2004 that "calling this struggle a war accurately describes the use of American and allied armed forces to find and destroy terrorist groups and their allies in the field."
But the phrase was always imperfect. We cannot defeat terrorism, the critics argued, because it is a tactic, or method. Hence, a war on terrorism is a misnomer at best, and would be futile at worst.
Perhaps persuaded by this view, some in the Obama administration initially encouraged use of the phrase "overseas contingency operations" instead of "global war on terrorism." But others, among them Leon Panetta, disagreed. "There's no question this is a war," he bluntly said of the post-9/11 conflict. Truth be told, the Bush administration itself wrestled with what to call the campaigns. Almost three years after 9/11, Donald Rumsfeld asked, "Are we fighting a global war on terror? Or are we witnessing a global civil war within the Muslim religion ... Or are we engaged in a global insurgency?"
The answer to each question is yes, which means that the language of war is appropriate.
Although defeating a method or an "ism" is more difficult than defeating a nation-state, the civilized world has, in effect, waged war against uncivilized behavior and methods in the past. Historian John Lewis Gaddis points to slavery, piracy and genocide - tactics or methods that were once condoned and even employed by the civilized world, but now are not. To be sure, these scourges still exist, but each is rare in today's world - rarer than they were in past centuries, and rarer than terrorism is today.
By destroying terror networks, eliminating or reforming regimes that deal in terror, and targeting the safe havens of terror, a successful war on terrorism could make this scourge "as obsolete as slavery, piracy or genocide," Gaddis argues. In other words, a war on terrorism is not necessarily a futile enterprise.
The debate over what to call this conflict has historical precedent. The authors of "NSC-68," a pivotal national-security document penned in 1950 to provide a roadmap for the struggle against Soviet communism, argued that success depended on recognition by "all free peoples" that the Cold War "is in fact a real war in which the survival of the free world is at stake."
To be sure, the war on terrorism is comprised of far more than military operations. As in the Cold War, intelligence agencies, law enforcement, development and diplomacy play important parts. However, these are supporting parts, because we are dealing with a tenacious military adversary.
Tellingly, President Barack Obama used the word "war" eight times in announcing the bin Laden strike.
That brings us to a second post-9/11 reality. Something close to a national consensus has emerged.
An open-ended war was unimaginable on Sept. 10, 2001. Yet a decade later, Americans have ratified the war on terrorism in multiple elections. And despite all the rhetoric, there is a remarkable amount of continuity between the Bush and Obama administrations on war policy, with the latter employing largely the same means to pursue the same ends as the former.
Third, the Middle East is no longer firewalled from freedom.
In 2001, the dominant - and seemingly unchangeable and unchallengeable - form of government in the Middle East was despotism. Saddam Hussein's Iraq represented the horrific end of the spectrum, Hosni Mubarak's Egypt the merely objectionable end. The only alternatives seemed to be the violent fundamentalisms of Iran, bin Laden and the Taliban - each representing a form of tyranny.
Ten years later, Iraq is no longer ruled by a tyrant; Afghanistan is no longer run by terrorists; Egypt and Tunisia have ousted their autocrats; a ragtag army of Libyan rebels, with the help of NATO's air armada, have ended Qaddafi's reign; despots are under pressure in Iran and Syria; and it is freedom that seems inevitable.
Make no mistake: there is a correlation between the war on terrorism and the emergence of free government in the heart of the Middle East. As Adm. Eric Olson, former commander of Special Operations Command, argues, the bin Laden takedown and the anti-autocracy revolutions combined for a staggering one-two punch at the old order. "The Arab Spring was a roundhouse. It took away the ideological message that you need violence to overthrow a government," he says. "The death of bin Laden was the upper cut to the jaw."
The result: "al-Qaida Version 1.0 is nearing its end," in Olson's view.
But that means that al-Qaida Version 2.0 is coming online, which brings us to a fourth reality. Although Afghanistan remains a deadly warzone, it may no longer be the central front of the war on terrorism.
After all, bin laden was found in Pakistan. Moreover, al-Qaida 2.0 is using Yemen and Somalia to target the United States. They haven't been successful, but they've come close.
That's why the U.S. military's efforts overseas - what some troops call "the away game" - are so crucial. By taking the fight to the enemy, U.S. forces have taken away its sanctuaries, and shifted the battlefront away from our shores.
Finally, winning will take time. It was in 1996 that the CIA created a unit devoted solely to tracking and targeting bin Laden. But it wasn't until 2011 - 15 years later - that U.S. forces finally eliminated the one-man terror superpower, thus pulling the plug on al-Qaida 1.0.
It may take just as long to outlast, outwit and outfight Version 2.0.