"THE HORRIFYING images of desperate Afghans trying to get out of Kabul this week after the United States-backed government collapsed have evoked a major juncture in world history, as America turned away from the world. The truth of the matter is that the end of the American era had come much earlier.. The long-term sources of American weakness and decline are more domestic than international. The country will remain a great power for many years, but just how influential it will be depends on its ability to fix its internal problems, rather than its foreign policy.
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.. Afghanistan’s ultimate effect on geopolitics is likely to be small. ...America still has many economic and cultural advantages that few other countries can match.

The much bigger challenge to America’s global standing is domestic: American society is deeply polarised, and has found it difficult to find consensus on virtually anything. This polarisation started over conventional policy issues like taxes and abortion, but since then has metastasised into a bitter fight over cultural identity. The demand for recognition on the part of groups that feel they have been marginalised by elites was something I identified 30 years ago as an Achilles heel of modern democracy. Normally, a big external threat such as a global pandemic should be the occasion for citizens to rally around a common response; the covid-19 crisis served rather to deepen America's divisions, with social distancing, mask-wearing and now vaccinations being seen not as public-health measures but as political markers.

These conflicts have spread to all aspects of life, from sports to the brands of consumer products that red and blue Americans buy. The civic identity that took pride in America as a multiracial democracy in the post-civil rights era has been replaced by warring narratives over 1619 versus 1776—that is, whether the country is founded on slavery or the fight for freedom. This conflict extends to the separate realities each side believes it sees, realities in which the election in November 2020 was either one of the fairest in American history or else a massive fraud leading to an illegitimate presidency.
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The United States is not likely to regain its earlier hegemonic status, nor should it aspire to. What it can hope for is to sustain, with like-minded countries, a world order friendly to democratic values. Whether it can do this will depend not on short-term actions in Kabul, but on recovering a sense of national identity and purpose at home."

https://www.economist.com/by-invitation/2021/08/18/francis-fukuyama-on-the-end-of-american-hegemony

Question: How the US could regain a sense of national identity and purpose at home?