What America got right–and wrong–in the post-9/11 era

The terror attacks of September 11, 2001 radically altered the course of American history. They reshaped our politics and sense of security, sending the country on a completely different arc—from wars in Afghanistan and Iraq to the sweeping expansion of the national security apparatus. 25 years after that fateful day, has America learned the right lessons or do we risk repeating the mistakes of the post-9/11 era? Former Defense Secretary Mark Esper joins Ian Bremmer on GZERO World to reflect on how 9/11 changed America and the biggest lessons from the last 25 years of US foreign policy.

The attacks shattered Americans’ assumption that the country was fundamentally secure and made us much more aware of its vulnerability. Vigilance was a crucial lesson, Esper argues. But he also says that the post-9/11 era offers a warning about the limits of power. America has a tendency to overreach. The war in Afghanistan showed the danger of confusing military capability with political possibility and difficulty of trying to transform an entire society with sheer force. There’s also a risk of eroding the very freedoms we’re trying to protect in the name of national security. But maybe more importantly, Esper says that the Unites States' focus of so much resources on the war of terror took our attention off an even more serious threat: China.

"I think [a lesson of 9/11] that's often forgotten is keeping in mind what makes America great and that is our democracy and our values" Esper says, "Living in a democracy means we have to accept some risk when it comes to foreign threats and not sacrifice because we're afraid."