[6] He remained in Congress until 1999; at the time he was one of two surviving members of the large Democratic freshman class of 1965 (the other being John Conyers).

He is previously the president and director of the Woodrow Wilson International Center for Scholars, and was appointed to serve as the vice chair of the 9/11 Commission.

In 2000–2001, he served as the American member of the International Commission on Intervention and State Sovereignty, which prepared the U.N policy of Responsibility to Protect, adopted in 2005.

[7] He was appointed Co-Chair of the Blue Ribbon Commission on America's Nuclear Future from 2010 to 2012 alongside Brent Scowcroft.

[8] Hamilton serves as a co-chair of the National Security Preparedness Group (NSPG) at the Bipartisan Policy Center.

On February 25, 2011, Hamilton wrote a letter to President Barack Obama urging him to commute Jonathan Pollard's sentence to time served.

He also stated, "I have been acquainted for many years with members of his family, especially his parents, and I know how much pain and anguish they have suffered because of their son's incarceration."

[21] Lee H. Hamilton serves as an honorary co-chair for the World Justice Project, an organization that works to strengthen the rule of law worldwide.

The moniker is largely symbolic, as locals generally do not refer to the road by that name, although the name is used frequently by the traffic reporter for the area's largest radio station, WHAS 840-AM in nearby Louisville, Kentucky.

In November 2015, Hamilton was awarded the Presidential Medal of Freedom by President Barack Obama in a ceremony at the White House.

[24][25] In 2018, Indiana University Bloomington announced that the School of Global and International Studies will be renamed the Hamilton Lugar School of Global and International Studies in honor of Hamilton and former U.S. senator Richard Lugar, describing both as "two immensely accomplished Indiana statesmen and two of the nation's most distinguished and influential voices in foreign policy.