The White House recently whispered out the back door that President Obama would not appear in Pennsylvania next Tuesday at the ceremonies for the 150th anniversary of Abraham Lincoln's Gettysburg Address. The political betting had been that this was a big-speech venue whose glow Mr. Obama would not want to miss. The higher-road expectation was that this particular Civil War anniversary required the presence of this particular American president. It's not happening. The administration's official attendee will be Secretary of the Interior Sally Jewell.

The White House offered no explanation beyond Jay Carney's bloodless reply to a reporter: "I think Americans will take the appropriate time to consider the speech that was delivered there. I would simply say that I have no updates on the president's schedule."

What was he supposed to say? Once the president—or whoever—decided he wouldn't attend, no possible explanation was going to suffice for the Gettysburg no-show.

There is no inclination in this quarter to second-guess the White House's rationale for not attending. And maybe it's just as well we won't hear Mr. Obama's thoughts on the Gettysburg Address. Those words were about a renewal of the nation's unity, and five years into the Obama presidency, the United States is about as politically divided as it can get. The division is so intense that Americans paint their political beliefs in one of two colors: blue or red.

That this division exists in 2013, 150 years after Lincoln wrote those words, is ironic, to say the least. So it is unavoidable that any reflection on the anniversary of the ceremony at Gettysburg Cemetery in 1863 has to occur inside the context of the nation's current presidency and what that presidency stands for.