The Gettysburg Address, Abraham Lincoln’s undying call for a “new birth of freedom” at the bloody turning point of the US Civil War, turns 150 years old Tuesday, even as the union he fought to preserve quarrels bitterly over the role of government.

The anniversary celebrations at the Soldiers’ National Cemetery in Gettysburg, where Lincoln delivered the 272 words that now count as one of the most revered speeches in US history, are expected to attract dignitaries, tourists and Civil War buffs.

President Barack Obama, the country’s first African American president, is staying away, however, embroiled in a struggle to save his signature health care reforms.

Civil War historian James McPherson and Secretary of the Interior Sally Jewell will give speeches, 21 immigrants will be sworn in as new US citizens, and an actor dressed as Lincoln will re-enact the famous address.

Slavery, the Confederacy, the Union, the Constitution, the Declaration of Independence — none rate so much as a mention in Lincoln’s restrained, eloquent text.

Yet in a little more than two minutes, Lincoln succeeded in re-centering the American project on the values of freedom, equality and democracy, less than a year after the emancipation of the slaves.

He pledged that “this nation, under God, shall have a new birth of freedom — and that government of the people, by the people, for the people, shall not perish from the earth.”

Lincoln delivered the address on November 19, 1863, more than four months after the armies of Union General George Meade and his Confederate counterpart Robert E. Lee collided on July 1 in Gettysburg, a market town in rural Pennsylvania of little strategic importance.

After three days of fighting, more than 50,000 soldiers on both sides were dead, wounded or missing. Lee escaped with the remnants of his army, his bold gamble on an invasion of the North undone and the Confederate cause all but finished.

The speech was so short, it was over before many of the dignitaries crowding the stage with Lincoln realized it had begun.

By the next day, versions of the speech appeared in the major northern newspapers, and many commentators hailed it as a work of genius, Reidy said.

Today, the speech may be better known than the battle that inspired it — memorized by schoolchildren and savored by historians for its classical allusions and subtle currents of meaning.

How much water it still holds with the country’s political elites is another matter.

Harvard University President Drew Gilpin Faust, writing in the Washington Post, pointed to the rapid growth of inequality in the United States, along with the erosion of educational opportunity and social mobility.

The responsibilities Lincoln set forth “belong to us still,” she said. “Yet on the 150th anniversary of Lincoln’s immortal speech, where is our stewardship of that legacy?”

Lincoln came to his Gettysburg moment amid the strife and confusion of war.

He went to Soldiers’ National Cemetery with an exacting brief: eulogize the dead, recommit the country to the war and prepare it to build a more expansive democracy with African Americans as equals.

His dedicatory “remarks” were added to the program almost as an afterthought, with top billing going to Edward Everett, a former secretary of state who was famous for his battlefield orations.

Everett wrote to the president the following day. He would be flattered, Everett said, if “I came as near to the central idea of the occasion, in two hours, as you did in two minutes.”

Lincoln responded he was happy his speech was “not a total failure.”

jm/sst