Addressing the nation from a hangar at Bagram Air Field in Afghanistan, President Obama declared tonight that, after a decade of war, the U.S. can "see the light of a new day on the horizon."

"The Iraq War is over. The number of our troops in harm's way has been cut in half, and more will be coming home soon. We have a clear path to fulfill our mission in Afghanistan, while delivering justice to al Qaeda," the president said on the one-year anniversary of the killing of Osama bin Laden. (Coincidentally also the nine-year anniversary of President George W. Bush's infamous "Mission Accomplished" speech.)

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With the president and his campaign pushing his national security credentials in recent days - even suggesting that GOP presidential candidate Mitt Romney would not have given the order to take out bin Laden - the president took credit for a strategy in Afghanistan that he said was succeeding, and painted a picture of a war that was ending more than two and a half years before the final U.S. troops are scheduled to leave.

"Over the last three years, the tide has turned," the president said while standing before a backdrop of MRAPs. "We broke the Taliban's momentum. We've built strong Afghan Security Forces. We devastated al Qaeda's leadership, taking out over 20 of their top 30 leaders. And one year ago, from a base here in Afghanistan, our troops launched the operation that killed Osama bin Laden. The goal that I set - to defeat al Qaeda, and deny it a chance to rebuild - is within reach."

The president's remarks, the first ever live presidential address to the nation from inside a warzone, capped his surprise visit to Afghanistan. Earlier in the day the president met with Afghan President Hamid Karzai and signed a Strategic Partnership Agreement that outlines the 10-year relationship between the U.S. and Afghanistan after the American withdrawal. Through 2024.

A senior administration official said the length commitment was because "we've learned, importantly, the rule of 1989, and that's obviously clear in this document. In that year, the international community abandoned Afghanistan to years of civil war, which was followed obviously by Taliban rule. That is a mistake that we will not repeat. This agreement will make clear to the Taliban, to al Qaeda, and to other international terrorist groups that they cannot wait us out. "

Or, as the president put it, "the agreement we signed today sends a clear message to the Afghan people: as you stand up, you will not stand alone. It establishes the basis of our cooperation over the next decade, including shared commitments to combat terrorism and strengthen democratic institutions. It supports Afghan efforts to advance development and dignity for their people. And it includes Afghan commitments to transparency and accountability, and to protect the human rights of all Afghans."

Go Behind the Scenes of the President's Secret Trip

The president said his administration would work with the Afghans "to determine what support they need to accomplish two narrow security missions beyond 2014: counter-terrorism and continued training. But we will not build permanent bases in this country, nor will we be patrolling its cities and mountains."

The U.S. and its NATO allies are set to hand off security control to the Afghans by the end of 2014. The U.S. is expected to shrink its force in Afghanistan from roughly 88,000 troops down to 68,000 by the end of September.

With polls indicating that 2/3rds of the American people do not believe the war in Afghanistan has been worth the cost, the president said, "I recognize that many Americans are tired of war. As President, nothing is more wrenching than signing a letter to a family of the fallen, or looking in the eyes of a child who will grow up without a mother or father. I will not keep Americans in harm's way a single day longer than is absolutely required for our national security. But we must finish the job we started in Afghanistan, and end this war responsibly."

The president, who spent time greeting troops earlier today, also thanked U.S. forces for their service. "This future is only within reach because of our men and women in uniform. Time and again, they have answered the call to serve in distant and dangerous places. In an age when so many institutions have come up short, these Americans stood tall. They met their responsibilities to one another, and the flag they serve under. I just met with some of them, and told them that as Commander-in-Chief, I could not be prouder. In their faces, we see what is best in ourselves and our country."

-Jake Tapper and Mary Bruce