Good summary of the increased divide in America and the ongoing political implications:

But recent survey data provides troubling evidence that a shared sense of national identity is unraveling, with two mutually exclusive narratives emerging along party lines. At the heart of this divide are opposing reactions to changing demographics and culture. The shock waves from these transformations — harnessed effectively by Donald Trump’s campaign — are reorienting the political parties from the more familiar liberal-versus-conservative alignment to new poles of cultural pluralism and monism.

An Associated Press-NORC poll found nearly mirror-opposite partisan reactions to the question of what kind of culture is important for American identity. Sixty-six percent of Democrats, compared with only 35 percent of Republicans, said the mixing of cultures and values from around the world was extremely or very important to American identity. Similarly, 64 percent of Republicans, compared with 32 percent of Democrats, saw a culture grounded in Christian religious beliefs as extremely or very important.

These divergent orientations can also be seen in a recent poll by P.R.R.I. that explored partisan perceptions of which groups are facing discrimination in the country. Like Americans overall, large majorities of Democrats believe minority groups such as African-Americans, immigrants, Muslims and gay and transgender people face a lot of discrimination in the country. Only about one in five Democrats say that majority groups such as Christians or whites face a lot of discrimination.

Republicans, on the other hand, are much less likely than Democrats to believe any minority group faces a lot of discrimination, and they believe Christians and whites face roughly as much discrimination as immigrants, Muslims and gay and transgender people. Moreover, only 27 percent of Republicans say blacks experience a lot of discrimination, while 43 percent say whites do and 48 percent say the same of Christians.

Taken as a whole, these partisan portraits highlight contrasting responses to the country’s changing demographics and culture, especially over the past decade as the country has ceased to be a majority white Christian nation — from 54 percent in 2008 to 43 percent today. Democrats — only 29 percent of whom are white and Christian — are embracing these changes as central to their vision of an evolving American identity that is strengthened and renewed by diversity. By contrast, Republicans — nearly three-quarters of whom identify as white and Christian — see these changes eroding a core white Christian American identity and perceive themselves to be under siege as the country changes around them.

Americans of both political parties sense the unraveling of a broadly shared consensus of American identity, although they cite different reasons for feeling that way. About seven in 10 Republicans and Democrats fear that the United States is losing its national identity, the A.P.-NORC survey found. The two political parties may not share much, but each is increasingly aware that the other has embraced a radically different vision of America’s identity and future.

These responses are shifting the political magnetic field that defines the parties. Republican leaders are finding strong support among their base for the Trump administration’s executive order barring travel to the United States from particular Muslim-majority countries. But their plan to repeal and replace the Affordable Care Act was dramatically derailed by factions within their own party.

Democrats, on the other hand, are enjoying energetic backing from their base for pro-immigration and pro-L.G.B.T. stances, but they are experiencing increasing opposition to their support for free trade.

There have been other times in our history when the fabric of American identity was stretched in similar ways — the Civil War, heightened levels of immigration at the turn of the 20th century and the cultural upheavals of the 1960s.

But during these eras, white Christians were still secure as a demographic and cultural majority in the nation. The question at stake was whether they were going to make room for new groups at a table they still owned. Typically, a group would gain its seat in exchange for assimilation to the majority culture. But as white Christians have slipped from the majority over the past decade, this familiar strategy is no longer viable.

White Christians are today struggling to face a new reality: the inevitable surrender of table ownership in exchange for an equal seat. And it’s this new higher-stakes challenge that is fueling the great partisan reorientation we are witnessing today.

The temptation for the Republican Party, especially with Donald Trump in the White House, is to double down on a form of white Christian nationalism, which treats racial and religious identity as tribal markers and defends a shrinking demographic with increasingly autocratic assertions of power.

For its part, the Democratic Party is contending with the difficulties of organizing its more diverse coalition while facing its own tribal temptations to embrace an identity politics that has room to celebrate every group except whites who strongly identify as Christian. If this realignment continues, left out of this opposition will be a significant number of whites who are both wary of white Christian nationalism and weary of feeling discounted in the context of identity politics.

This end is not inevitable, but if we are to continue to make one out of many, leaders of both parties will have to step back from the reactivity of the present and take up the more arduous task of weaving a new national narrative in which all Americans can see themselves.