There's a reason President Obama chose Colorado to hold a rally this Wednesday in favor of gun control.
Among the states this year, Democratic-controlled Colorado has passed the toughest new restrictions on gun rights, requiring universal background checks and banning magazines that hold more than 15 rounds of ammunition.
But if certain liberal wishes have come true in Colorado -- recall that it was one of two states last fall that voted to legalize marijuana -- things look very different next door in Kansas.
A rafter of conservative legislation has been moving in Kansas this year, including a measure that allows people to carry concealed weapons into public buildings. The Republican-dominated government also has put new restrictions on abortion and made it harder for teachers to donate to union political activities.
"I live probably about 12 miles from Kansas," says Greg Brophy, a Republican state senator from eastern Colorado. "I like Colorado better, but I have to admit their [Kansas'] politics has more appeal to me right now, that's for sure."
A 'New Phenomenon'
This sort of dynamic is playing out across the country. On a wide variety of issues -- gay marriage, tax policy, implementing Obamacare, the death penalty -- states are moving in polar opposite directions from one another.
"This is very much a new phenomenon, drawing really clear lines between the states," says Ray Scheppach, former executive director of the National Governors Association.
Those divisions mean people are living in political cultures that are starting to look entirely different from one another. That's likely to polarize the nation's politics even further.
"Most of the policy [innovation] has come from the states, but we've never had a country that's so ideologically segmented as it is right now," says Susan MacManus, a University of South Florida political scientist.
How It Happened
By now, the notion that most states are either Democratic "blue" or Republican "red" is a fairly shopworn idea. But it's increasingly true. Even as presidential voting has remained reasonably close on a national level, the states are split far apart.
Last year, Obama won nationally by four percentage points, but the winning margin of victory for either candidate was under 5 percent in only four states (Florida, North Carolina, Ohio and Virginia). Victory was totally lopsided in half the states, with margins of more than 15 percent.
States are just as divided internally. In last year's elections, blue states got bluer, while red states grew redder. The parties now share legislative control in only three states -- Iowa, Kentucky and New Hampshire -- which is the lowest number since 1944.
One party controls both the legislature and the governorship in all but a dozen states -- with veto-proof supermajority control in half the chambers nationwide. The result has been that legislation in most states now strongly comports with the wishes of one party or the other.
In prior years, new policies might have originated in either Democratic or Republican states, but they tended to spread eventually pretty much everywhere, regardless of partisan leanings, says Scheppach, who now teaches at the University of Virginia.
Now, though, states are following almost entirely separate and distinct tracks. "It's a new phenomenon and I don't think it's a particularly good one," he says. "It makes all politicians much more ideological, which means not negotiating out differences."
A Patchwork On Abortion
With the Supreme Court considering gay marriage, there's been a lot of speculation about whether justices would make policies uniform or let state laws differ.
There have been comparisons to the 1973 abortion decision in Roe v. Wade, which appeared to set a national standard but has in fact triggered a wide variance among states, as conservatives find new ways to limit abortion rights.
That's been especially true recently, with Republicans in states such as North Dakota and Arkansas passing strict limitations on abortions last month.
"For a woman who lives in New York, her constitutional rights around reproductive choices are just stronger than a woman who lives in Mississippi," says Julie Rikelman, director of litigation at the Center for Reproductive Rights.
A number of states have passed abortion restrictions over the past couple of years, while a few are looking into ways of expanding access to abortion. Washington state is considering a measure to require health insurers to pay for abortions, for instance, while California may increase the number of health professionals allowed to perform surgical abortions.
It's better for the states to undergo this sort of "tumultuous" sorting out of abortion policy than having the courts impose a single standard by fiat, says Dan McConchie, vice president for government affairs at Americans United for Life.
"The [Supreme] Court, by taking this out of the public sphere with Roe, actually created this trench warfare," he says. "Your only alternative is to let the democratic process work, even if that results in a patchwork."
It's Not Just Social Issues
Several red states are looking into abolishing income taxes altogether, while income taxes have been raised or might yet go up in places such as Maryland, Massachusetts and Minnesota.
Environmental policy also looks a lot different, depending on where you live. States have roughly split themselves in half over the past decade when it comes to the question of addressing climate change, or not.
Now, neighboring states such as Pennsylvania and New York are taking totally different approaches when it comes to allowing fracking for natural gas.
"It is a tale of two nations," says Barry Rabe, an expert on environmental policy at the University of Michigan. "We see states going in dramatically different directions."
It's happening on almost every issue.
"Ten years ago, you couldn't tell the difference between Republican and Democratic governors [on some issues]," says Scheppach, the former governors association official. "They're becoming more extensions of their respective parties, so I'm afraid that gulf is going to get larger."
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