As we take stock of the decade since 9/11, what have we learned?
The global response to September 11th and the subsequent "war on terror" largely defined politics in the 21st century.
In the past decade alone, we spent trillions of dollars and lost thousands of lives in pursuit of suspected terrorists and terror havens. In the process, we thwarted threats, captured militants, killed Osama bin Laden, and all but immobilized al-Qaeda.
Yet there have been many trade-offs.
Across Europe and the U.S., we built walls that confined us, and waged wars that defined us. We passed legislation that curtailed cherished freedoms and movement. Governments sponsored covert prisons abroad and sanctioned "waterboarding" and "extraordinary rendition."
Ten years on, analysts impart contentious lessons from 9/11 that may even be irreconcilable.
For some, 9/11 speaks to the perils of a weak security apparatus and a timid state. These views fueled an aggressive U.S. foreign policy in which war and even torture were portrayed as integral to peace.
Others see the lessons of 9/11 differently. They trace the roots of terrorism to unrest in the Middle East. Rather than wage war, they want America to promote democracy and free markets.
Isolationists take a different view. They see the post-9/11 period as underlining the perils of imperial overstretch. Rather than wage war, they want America to resettle its sights on domestic priorities.
Still others say 9/11 teaches the need for multilaterialism. Rather than act unilaterally, America must work together with allies. After all, 9/11 united the world as never before. Terrorism can only be defeated, they say, by recognizing our common humanity.
As you reflect on the past decade, what did you learn from 9/11?
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