This post originally ran on Robert Reich’s Web page, www.robertreich.org

Soon after President Obama’s second inaugural address, John Boehner said the White House would try “to annihilate the Republican Party” and “shove us into the dustbin of history.”

Actually, the GOP is doing a pretty good job annihilating itself. As Louisiana Governor Bobby Jindal put it, Republicans need to “stop being the stupid party.”

The GOP crackup was probably inevitable. Inconsistencies and tensions within the GOP have been growing for years – ever since Ronald Reagan put together the coalition that became the modern Republican Party.

All President Obama has done is finally find ways to exploit these inconsistencies.

Republican libertarians have never got along with social conservatives, who want to impose their own morality on everyone else.

Shrink-the-government fanatics in the GOP have never seen eye-to-eye with deficit hawks, who don’t mind raising taxes as long as the extra revenues help reduce the size of the deficit.

The GOP’s big business and Wall Street wing has never been comfortable with the nativists and racists in the Party who want to exclude immigrants and prevent minorities from getting ahead.

And right-wing populists have never got along with big business and Wall Street, which love government as long as it gives them subsidies, tax benefits, and bailouts.

Ronald Reagan papered over these differences with a happy anti-big-government nationalism. His patriotic imagery inspired the nativists and social conservatives. He gave big business and Wall Street massive military spending. And his anti-government rhetoric delighted the Party’s libertarians and right-wing populists.

But Reagan’s coalition remained fragile. It depended fundamentally on creating a common enemy: communists and terrorists abroad, liberals and people of color at home.

On the surface Reagan’s GOP celebrated Norman Rockwell’s traditional, white middle-class, small-town America. Below the surface it stoked fires of fear and hate of “others” who threatened this idealized portrait.

In his first term Barack Obama seemed the perfect foil: A black man, a big- spending liberal, perhaps (they hissed) not even an American.

Republicans accused him of being insufficiently patriotic. Right-wing TV and radio snarled he secretly wanted to take over America, suspend our rights. Mitch McConnell declared that unseating him was his party’s first priority.

But it didn’t work. The 2012 Republican primaries exposed all the cracks and fissures in the GOP coalition.

The Party offered up a Star Wars barroom of oddball characters, each representing a different faction — Bachmann, Perry, Gingrich, Cain, Santorum. Each rose on the strength of supporters and then promptly fell when the rest of the Party got a good look.

Finally, desperately, the GOP turned to a chameleon — Mitt Romney — who appeared acceptable to every faction because he had no convictions of his own. But Romney couldn’t survive the general election because the public saw him for what he was: synthetic and inauthentic.

The 2012 election exposed something else about the GOP: it’s utter lack of touch with reality, its bizarre incapacity to see and understand what was happening in the country. Think of Karl Rove’s delirium on Fox election night.

All of which has given Obama the perfect opening — perhaps the opening he’d been waiting for all along.

Obama’s focus in his second inaugural — and, by inference, in his second term — on equal opportunity is hardly a radical agenda. But it aggravates all the tensions inside the GOP. And it leaves the GOP without an overriding target to maintain its fragile coalition.

In hammering home the need for the rich to contribute a fair share in order to ensure equal opportunity, and for anyone in America — be they poor, black, gay, immigrant, women, or average working person — to be able to make the most of themselves, Obama advances the founding ideals of America in such way that the Republican Party is incapable of opposing yet also incapable of uniting behind.

History and demographics are on the side of the Democrats, but history and demography have been on the Democrats’ side for decades. What’s new is the Republican crackup — opening the way for a new Democratic coalition of socially-liberal young people, women, minorities, middle-class professionals, and what’s left of the anti-corporate working class.

If Obama remains as clear and combative as he has been since Election Day, his second term may be noted not only for its accomplishment but also for finally unraveling what Reagan put together. In other words, John Boehner’s fear may be well-founded.

Robert B. Reich, chancellor’s professor of public policy at UC Berkeley, was secretary of labor in the Clinton administration. Time magazine named him one of the 10 most effective Cabinet secretaries of the last century. He has written 13 books, including the best-sellers “Aftershock” and “The Work of Nations.” His latest, “Beyond Outrage,” is now out in paperback. He is also a founding editor of The American Prospect magazine and chairman of Common Cause.