The Sept. 11, 2001, terrorist attacks were such a unifying event for modern Americans, and nothing else has come close to being as important or as memorable, according to a new survey conducted by Pew Research Center.

Roughly three-quarters (76%) of the public include the Sept. 11 terror attacks as one of the 10 events during their lifetime with the greatest impact on the country, according to a national online survey of 2,025 adults conducted June 16-July 4, 2016.

According to the survey, while the Sept. 11 attacks easily top the list for whites, it shares the top spot with the election of Barack Obama among blacks. Similarly, the civil rights movement ranks behind only the election of Obama and 9/11 on the list of most significant events for blacks but is absent from the top 10 lifetime events for whites.

Just as striking as the public’s consensus on the impact of 9/11 is the steep drop-off in the proportion of Americans who name other notable events. The election of Obama is the second-most frequently named event, listed by 40% of the public. Every other event is named by fewer than one-quarter of all adults. This includes the changes ushered in by the internet, personal computers, smartphones and other innovations of the tech revolution, the assassination of John F. Kennedy, and the Vietnam War.

Survey participants were asked to list the 10 historic events that occurred during their lifetimes that they thought “have had the greatest impact on the country.” Respondents were further told that they could name a specific event, a series of related events or any other historic development that had a major influence on American life.

The survey finds that Americans are primarily bound together by their generation and the major events that occurred during their formative years. For the oldest Americans, the Silent and Greatest generations, that unifying event is World War II. For Baby Boomers, the assassination of John F. Kennedy and the Vietnam War are defining moments. For Millennials and Gen Xers, the 9/11 terror attacks and the Obama election leads the list by a greater margin than for other generations.

The top 10 list for these young Americans also varies from the rankings of other generations. For example, the Columbine school shooting makes the top 10 list of Millennials and Gen Xers but not Boomers or the Silent Generation. Millennials also are unique in that five of their top 10 events – the Sandy Hook and Orlando/Pulse nightclub shootings, the death of Osama bin Laden, the Boston Marathon bombing and the Great Recession – appear in no other generation’s top 10 list.

The public’s responses to two other survey questions are even more varied. When asked to name the historic event that made them feel the proudest of their country, the country’s collective response to Sept. 11 led the list, although it is only named by 19% of adults. The Obama election finishes a distant second with 14%, while the moon landing, the killing of bin Laden and the legalization of gay marriage receive single-digit support.