A Pew Research study finds that America has never been more polarized, and more than ever, it’s politics, not race or class, that divides us.

The study, which looks at trends in American values-based beliefs from 1987 through 2012 finds that the “values gap” between Republicans and Democrats has never been wider. As the poll’s top-line memo states: “Republicans are most distinguished by their increasingly minimalist views about the role of government and lack of support for environmentalism. Democrats have become more socially liberal and secular. Republicans and Democrats are most similar in their level of political engagement.”

Among the key findings:

• The average partisan gap on values issues has doubled from 1987 to 2012, from 10 percent to 18 percent.
• Nearly all of the increases have taken place during the George W. Bush and Barack Obama presidencies, and during both terms, the base of the respective parties have criticized their party for not standing up for traditional partisan beliefs. According to the poll, in the current survey, 71 percent of Republicans and 58 percent of Democrats say their parties have done a poor job standing up for their traditional beliefs.
• Over the last 25 years, both parties have become smaller, and more “ideologically homogeneous.” Among Republicans, conservatives now outnumber moderates by two-two one, and among Democrats, there are now just as many liberals as moderates.
• Gender, race, ethnic, religious and class divisions on values have remained stable. and while there are differences between the value systems of the highly religious and the less religious, and between the more and less educated, those differences “pale in comparison to the overwhelming partisan divide we see today.
• While there are more political “independents” than ever, most independents actually lean toward one or the other political party, and when those independents are included, the “values gap” is just as wide as when they are left out.
• Republicans have shifted sharply toward a belief in a limited role for government, and Republicans have turned increasingly against the idea of a social safety net, and the concept that the government should help those who cannot care for themselves. Republicans have also become more anti-immigration over time.
• Democrats increasingly believe that society should work to assist minorities, while Republicans have remained as opposed today as they were in the 1980s, leading to a wider gap between the two parties on the question of racial preferences.

From the poll writeup by Pew researcher Andrew Kohut:

Republicans and Democrats are furthest apart in their opinions about the social safety net. There are partisan differences of 35 points or more in opinions about the government’s responsibility to care for the poor, whether the government should help more needy people if it means adding to the debt and whether the government should guarantee all citizens enough to eat and a place to sleep.

On all three measures, the percentage of Republicans asserting a government responsibility to aid the poor has fallen in recent years to 25-year lows.

Just 40 percent of Republicans agree that “It is the responsibility of the government to take care of people who can’t take care of themselves,” down 18 points since 2007. In three surveys during the George W. Bush administration, no fewer than half of Republicans said the government had a responsibility to care for those unable to care for themselves. In 1987, during the Ronald Reagan’s second term, 62 percent expressed this view.

Over the past two decades, the public consensus in favor of tougher environmental restrictions has weakened, also primarily because of changing opinions among Republicans.

For the first time in a Pew Research Center political values survey, only about half of Republicans (47 percent) agree that “there needs to be stricter laws and regulations to protect the environment.” This represents a decline of 17 points since 2009 and a fall of nearly 40 points, from 86 percent, since 1992.

The partisan gap over this measure was modest two decades ago. Today, roughly twice as many Democrats as Republicans say stricter environmental laws and regulations are needed (93 percent vs. 47 percent).

At the same time the poll finds that Democrats have shifted in their values too, though less dramatically than Republicans. Today, the number of Democrats who say the “never doubt the existence of God” has fallen 11 points in a decade, to 77 percent (76 percent for independents) and the percentage of white Democrats who express no doubt on God’s existence has declined 17 percent, to 68 percent.

Democrats have also shifted to become more favorable toward immigration, and toward alternatives to traditional marriage. Today, just 6 in 10 Democrats say they have “old fashioned values about family and marriage,” down from 70 percent in 2007 and from 86 percent in 1987. For Republicans, that number is closer to 9 in 10, with 88 percent of respondents professing old fashioned values about marriage.

On the question of “doing whatever is necessary to improve the position of minorities,” including support for race-based preferences, just over half of Democrats are in support (52 percent), which is an 11 percent increase just since 2007 in those who say “we should make every effort to improve the position of blacks and other minorities, even if it means giving them preferential treatment.” For Republicans, just 12 percent agree with that statement, a stable percentage over time, which means the gap between Republicans and Democrats on the issue of racial preferences has grown from 18 percentage points in 1987, to 40 points today.