President Barack Obama’s unannounced trip to Afghanistan served official purposes, allowing him to sign, on Afghan soil, an agreement spelling out U.S. involvement in the country following the withdrawal of NATO troops in 2014.

Mandel Ngan / AFP - Getty Images

President Barack Obama and Afghan President Hamid Karzai sign a strategic partnership agreement on May 1 at the Presidential Palace in Kabul.

There was no campaign build-up surrounding the trip, and the secrecy in which the mission was conducted – utilizing the cover of darkness to help shepherd Obama safely into the active war zone – hardly set it apart from Obama’s other trips to Afghanistan or Iraq.

But after the campaign between the Democratic incumbent and Republican foe Mitt Romney was subsumed by a spat over how much credit the president deserves for authorizing the successful mission to kill Osama bin Laden a year ago to the day – and whether his Republican rival would have authorized the same mission – Tuesday’s trip by Obama sends an unmistakable message: there is only one commander in chief.

“No political objections. This is what commanders in chief are supposed to do," said Ari Fleischer,  the press secretary to President George W. Bush in 2001, when the al Qaeda attacks were launched against New York and Washington. "Just think how much better it could have been for the president if he never did the attack Romney ad."

"I think it's always good when the president goes to where young men and women are in harm's way," Sen. John McCain, R-Ariz., told CNN Tuesday afternoon.

The 2008 Republican presidential nominee has been an outspoken critic of the way Obama has used the bin Laden killing as a political chit. He said he couldn't accuse Obama of making the trip to Afghanistan for political purposes, and didn't view it as excessively celebratory.

Obama will address the nation this evening, live from Afghanistan, where his remarks will make reference to the bin Laden anniversary, according to pool reporters traveling with the president.

“I hardly think that you’ve seen any excessive celebration taking place here,” Obama said Monday at the White House in response to Republican criticism that the president’s campaign was too celebratory in marking the anniversary.

“I think for us to use that time for some reflection to give thanks to those who participated is entirely appropriate, and that's what’s been taking place,” Obama added.

The “Strategic Partnership Agreement” being signed Tuesday by Obama and Hamid Karzai, his Afghan counterpart, pledges continued U.S. support for Afghanistan after NATO’s mission there ends in 2014. It doesn’t speak to troop or funding levels, but rather looks to install a framework for an organized withdrawal of international forces in hopes of avoiding strife.

But it’s still difficult to divorce those very serious goals from the political implications of this visit; in truth, Obama’s trip to Afghanistan does reinforce his image as a commander in chief, even if that outcome were entirely unintended by the White House.

And the Romney campaign is mindful of that powerful imagery.

Their acute sense of these national security politics were on display Tuesday when Romney joined former New York City Mayor Rudy Giuliani, whose legacy is forever tied to his handling of the bin Laden-directed attacks on lower Manhattan. They met at a firehouse that suffered particularly steep losses on Sept. 11, 2001, and hailed the president for authorizing the mission.

“I acknowledged a year ago that the president deserves credit for the decision he made, and I continue to believe that, and certainly would have taken that action myself,” said Romney, alongside Giuliani.

But the former Massachusetts governor didn’t entirely steer clear of challenging Obama’s foreign policy gravitas, either.

“I think I said the same thing then as … Joe Biden,” Romney said in reference to his own skepticism in 2007 of whether it was worth leveraging all of the resources in the U.S. to find bin Laden. “It was naive of the president to announce he would go into Pakistan. We always reserve the right to go anywhere to get Osama bin Laden.”

And today, in an official trip that squarely framed the president as America’s top military official, Obama went to that same corner of the world to mark the one-year anniversary of having done just that.