Another culprit is the increasing economic stress felt by most middle-class Americans. Median household incomes are dropping and over three-quarters of Americans report they're living paycheck to paycheck.
It's easier to be generous and expansive about the sphere of "we" when incomes are rising and future prospects seem even better, as during the first three decades after World War II when America declared war on poverty and expanded civil rights. But since the late 1970s, as most paychecks have flattened or declined, adjusted for inflation, many in the stressed middle no longer want to pay for "them."
Yet this doesn't explain why so many wealthy America's are also exiting. They've never been richer. Surely they can afford a larger "we." But most of today's rich adamantly refuse to pay anything close to the tax rate America's wealthy accepted 40 years ago.
Perhaps it's because, as inequality has widened and class divisions have hardened, America's wealthy no longer have any idea how the other half lives.
Being rich in today's America means not having to come across anyone who isn't. Exclusive prep schools, elite colleges, private jets, gated communities, tony resorts, symphony halls and opera houses, and vacation homes in the Hamptons and other exclusive vacation sites all insulate them from the rabble.
America's wealthy increasingly inhabit a different country from the one "they" inhabit, and America's less fortunate seem as foreign as do the needy inhabitants of another country.
The first step in widening the sphere of "we" is to break down the barriers -- not just of race, but also, increasingly, of class, and of geographical segregation by income -- that are pushing "we Americans" further and further apart.
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