Along with — and because of — dramatic social and demographic changes, America is quickly dividing itself into two separate nations, regional enclaves of rigid politics, as the idea of common national priorities fades further into a distant past.

Rich Morin, a senior editor at the Pew Research Center, wrote about a new study on public opinion on Wednesday and found that:“Americans often say they want their representatives in Congress to put the country’s needs over local concerns. But four novel experiments suggest that the public does just the opposite.”He continued:“Respondents rated a member of Congress far more favorably if the lawmaker put the interests of his or her district or state over those of the country as a whole.”He concluded, in part, with this damning line:“The study’s author says legislators who ‘nobly’ put national preferences ahead of local ones will be punished by constituents.”Here’s why this is so problematic: on a state level, and even on a county and community level, we as a country continue to self-sort into ideological islands.

According to the author Bill Bishop, who in 2008 published “The Big Sort: Why the Clustering of Like-Minded America is Tearing Us Apart”:“In 1976, only about a quarter of America’s voters lived in a county a presidential candidate won by a landslide margin. By 2004, it was nearly half.”And the country’s seismic demographic and cultural shifts threaten to make our tribalism permanent.

There has been the rapid rise of minority populations and stagnation in the growth of the non-Hispanic white population in this country. Now, Hispanics represent a majority of all births in America, and last week The New York Times reported on census data that revealed that “deaths exceeded births among non-Hispanic white Americans for the first time in at least a century.”In fact, according to an Associated Press report last week, which cited government reports: “For the first time, America’s racial and ethnic minorities now make up about half of the under-5 age group.”But there were also some worrisome statistics in the report that could help to signal those children’s views on policy. According to the report: “Black toddlers were most likely to be poor, at 41 percent, followed by Hispanics at 32 percent and whites at 13 percent. Asian toddlers had a poverty rate of 11 percent.”As a Pew Research Center report found in 2009, while top earners (those earning $100,000 or more) were almost evenly split among Democrats, independents and Republicans, the lowest earners (those making $20,000 or less) were more than twice as likely to be Independents than Republicans, and were nearly three times as likely to be Democrats than Republicans.

Furthermore, what constitutes a family and who is seen as the head of that family has also changed. According to a March report titled “Knot Yet,” which was sponsored by The National Campaign to Prevent Teen and Unplanned Pregnancy, the Relate Institute and The National Marriage Project at the University of Virginia:“By age 25, 44 percent of women have had a baby, while only 38 percent have married; by the time they turn 30, about two-thirds of American women have had a baby, typically out of wedlock. Over all, 48 percent of first births are to unmarried women, most of them in their 20s.”In fact, the report found that “for women as a whole, the median age at first birth (25.7) now falls before the median age at first marriage (26.5), a phenomenon we call ‘The Great Crossover.’ ”But in almost every case, the states that went for Barack Obama in 2012 had the higher ages of first marriage, and the ones that went for Mitt Romney had lower ones.

It would stand to reason that attacks on contraception and a full range of family planning options — including a woman’s right to an abortion — might be viewed differently by these families.

And, we are becoming less blindly religious and more blindly militaristic. (The former is a good thing; the latter, not so much.)According to Gallup, the percentage of Americans saying that they have quite a lot or a great deal of confidence in “the church or organized religion” went from 68 percent in 1975 to 48 percent in 2013. Over the same period, those expressing the same amount of confidence in the military has gone from 58 percent to 76 percent.

This means that on the moral front, more liberal views — like support for same-sex marriage — are allowed to quickly spread and have gone from being seen as radical to mainstream. But even on this issue, we are becoming two Americas: one where same-sex marriage is legal in some states and another where it’s specifically outlawed.

But on the military front, it means that revelations about recent government snooping on Americans doesn’t sound as many alarms as it should have. Politically, it also means that some of the old ideological battle lines on national security have been scrambled so that Republicans no longer get all the credit, nor Democrats all the blame.

These new realities have changed the conversation about the role and size of government, about the line between individual liberty and the collective good, about the meaning of personal responsibility and societal responsibility.

They have also signaled that conservative arguments on many of these issues are losing their resonance nationally, and that the Republican pool of potential voters is shrinking while the Democratic pool expands.

So, to defend themselves, their ways of thinking (and, to their minds, their way of life), Republicans are pulling every lever to slow the change on the state level — gerrymandering, limiting voter access, passing anti-immigrant laws, cutting assistance to the poor.

This means we’re now at a point where people may not worry as much about all of America as about their slice of America. In the tumult and transition of change, we may be becoming a nation divided against itself.