The initial national unity observed immediately after the 9/11 attacks quickly dissipated, replaced by significant political divisions that continue to affect American society. While congressional leaders held a bipartisan ceremony reminiscent of the post-9/11 solidarity, this unity is now largely absent from the political landscape. Many observers note that the country has become more divided, with experts like Michael J. Allen of Northwestern University pointing out that the U.S. is less confident and optimistic than in September 2001, despite being more diverse and having a more realistic view of its challenges.

The first major cracks in post-9/11 unity appeared with the Bush administration's decision to invade Iraq, a country that played no role in the attacks. This foreign policy choice, supported by both Republican and prominent Democratic leaders, led to a period of political disillusionment. Concurrently, Muslim Americans faced widespread bigotry and were forced to defend their faith, further exacerbating societal fragmentation.

The fallout from the Iraq War contributed to a shift in political leadership, paving the way for the election of Barack Obama, who had publicly opposed the war. This period saw the emergence of a new political class, but one characterized by increased confrontation and a decline in public trust. This environment, experts suggest, ultimately contributed to the election of Donald Trump and has left Americans less capable of achieving consensus on critical issues, from the COVID-19 pandemic to climate change.

The decline in national pride and civic engagement is stark. After 9/11, roughly 70% of Americans were "extremely proud" of their country, a figure that has since plummeted to 33%, the lowest recorded by Gallup. Display of the American flag, once a symbol of unity with 79% public display post-9/11, is now significantly lower at 43%, with a partisan divide. The current political climate is marked by extreme polarization, where most Democrats and Republicans view members of the opposing party as immoral and dishonest, reflecting a significant deterioration from the perceived unity of September 2001.

Technological advancements, particularly the rise of social media, are also cited as a major factor in the changed national response. Experts believe that if 9/11 were to happen today, the public and political reaction would be vastly different due to the pervasive influence of digital platforms. The lasting impact of the attacks, a quarter-century later, continues to shape American life through ongoing grief, wars, and political Furies.