20 years later: The lasting impact of 9/11 on Congress

The American Flag flies at the U.S. Capitol in Washington, U.S., December 17, 2020. REUTERS/Tom Brenner

20th anniversary 9_11 graphic (1)Twenty years after the Sept. 11 terrorist attacks, the effects of the day still permeate policy and politics on Capitol Hill. The attacks altered Congress’s agenda, further encouraged lawmakers to cede questions of war to presidents, and revamped Capitol Hill’s security posture. The growth in congressional partisanship over the past two decades exacerbates these trends, further diminishing lawmakers’ incentives to protect and project their institutional roles in the making of war and foreign affairs. Here are three takeaways on the imprint of 9/11 on Congress today.

Revamping budgets and bureaucracies

The 9/11 attacks reshaped the business of Congress in at least two ways.

First, the attacks have had lasting effects on congressional budgeting for defense. According to the Congressional Research Service, the federal government spent an estimated $2 trillion in emergency funding to support its response to the 9/11 attacks; Other analysts tally the costs at over $6 trillion. Legislative critics on the left and right have at times derided such emergency monies as slush funds since Congress does not account for the funding in its regular appropriations, allowing it to evade spending limits put in place in 2011. But the parties have generally been complicit in exempting such amounts from legal limits placed on other avenues of government spending. Two decades later, Congress still affords special treatment to the fiscal demands of the government’s war on terror.

Second, in response to the crisis, Congress, over the early objections of President George W. Bush, engineered the largest reorganization of the federal government since World War II. The resulting Department of Homeland Security (DHS) consolidated 22 federal agencies, including parts of agencies without domestic security mandates. But while both chambers eventually established oversight committees for DHS, neither the House nor Senate revamped other committee jurisdictions to align with the new department. The mismatch leaves authority over homeland security in the hands of dozens of committees and subcommittees, diluting lawmakers’ effective oversight and making it harder to hold administrations accountable. What’s more, moving agencies like the Coast Guard or the old Immigration and Naturalization Service into DHS and giving them domestic security mandates diminished agency resources for the original mandates legislated by Congress.

Ceding war to presidents

Lawmakers have also placed themselves on weaker footing with respect to the president in the conduct of military operations overseas and foreign affairs more generally. Congress and the president together facilitated the expansion of executive power in the wake of 9/11 by enacting with overwhelming bipartisan support two authorizations for the use of military force (or AUMF) in 2001 and 2002. The first, passed just days after the 9/11 attacks, targeted the “nations, organizations, or persons he determines planned, authorized, committed, or aided the terrorist attacks that occurred on September 11, 2001, or harbored such organizations or persons.” The second, adopted in October 2002, applied to military operations in Iraq.

Presidents of both parties have since relied on the two resolutions to legally justify a broad range of overseas military actions beyond the wars in Iraq and Afghanistan. The Obama administration cited the 2001 measure in support of its 2016 airstrikes in Libya; the Trump administration pointed to the 2002 resolution when U.S. forces killed Iranian general Qassem Soleimani in 2020. A growing chorus of lawmakers in recent years have called for clawing back some of this power for Congress, and President Biden supports repealing the 2002 measure.

But over the past two decades, Congress has generally been comfortable letting the president use the power expansively with limited oversight: Legislators neither want to be seen as undermining national security nor blamed for potentially unpopular military operations. Keeping the AUMFs long past their shelf life allows lawmakers to fixate on the legality of the attacks while failing to hold presidents accountable for their policy choices—including those leading to the unfolding crisis following the U.S. withdrawal from Afghanistan.

Rethinking Capitol security

The physical security of the U.S. Capitol complex, and the physical safety of the tens of thousands of people who report to work there on an ordinary day, have been in the headlines since the attack on the Capitol on January 6, 2021, that disrupted the counting of the Electoral College votes. As Congress continues to consider additional changes to its security posture—as called for, by among others, U.S. Capitol Police officers who testified in July before the Select Committee to Investigate the January 6th Attack on the U.S. Capitol—it’s worth remembering that much of the groundwork for current policies and practices dates to post-9/11 changes.

For anyone who works on or visits Capitol Hill today, the changes made in the months and years immediately following the attack are readily apparent. Congress allocated funding to speed up the Capitol Visitors’ Center to serve as a security screening point for visitors to the Capitol itself; closed streets around congressional office buildings; constructed additional vehicle barriers; and made other changes to emergency procedures. By 2004, Congress had expanded the U.S. Capitol Police force (which today comprises almost 10% of the legislative branch’s budget) by roughly 27%.

These operational procedures were significant. But Congress left much bigger-picture, longer-range planning of importance undone. Despite calls for major reforms that would allow the House and Senate to continue operating and, if necessary, repopulate themselves in the event of catastrophe, Congress did little to address its own continuity.

Two decades later, the effects of 9/11 still permeate Congress—physically and politically.

This work is licensed under the Creative Commons Attribution-NonCommerical-NoDerivatives 4.0 International License. To view a copy of the license, visit