Obama and Vice President Joe Biden flew into Fort Campbell, Ky., to meet with those involved in the Abbottabad, Pakistan, Navy SEAL raid that left the founder and leader of the al-Qaida terrorist network dead.
A White House official said Obama and Biden were briefed on the operation and then "met with the full assault force that carried out the operation. The president awarded the units involved a Presidential Unit Citation -- the highest such honor that can be given to a unit -- in recognition of their extraordinary service and achievement."
Following the private meetings, Obama addressed about 2,200 soldiers and base personnel.
"I came here for a simple reason -- to say thank you on behalf of America. This has been a historic week in the life of our nation. Thanks to the incredible skill and courage of countless individuals -- intelligence, military -- over many years, the terrorist leader who struck our nation on 9/11 will never threaten America again."
The trip followed by one day Obama's visit to New York, where he laid a wreath at Ground Zero in memory of the nearly 3,000 people killed in the al-Qaida-orchestrated Sept. 11, 2001, attacks, which felled the World Trade Center towers, and met with 50 family members of victims.
"We will never forget," Obama told family members at New York's Ground Zero Thursday as he shook hands and offered hugs.
"When we say we will never forget, we mean what we say," Obama told members of New York's "Pride of Midtown" firehouse, who had the heaviest casualties of any station house in the city in the World Trade Center attack.
"When those (Navy SEALs) took those extraordinary risks going into Pakistan ... they were doing it in part because of the sacrifices that were made in the States," Obama said in front of a red Engine 54 fire truck. "They were doing it in the name of your brothers that were lost."
Among the 2,752 people who died in the World Trade Center attack, 343 were firefighters and 60 were police officers.
At Fort Campbell, Obama thanked members of SEAL Team Six, officially known as the U.S. Naval Special Warfare Development Group, who carried out the pre-dawn Monday raid on bin Laden's fortified compound.
Team Six, based at the Naval Air Station Oceana Dam Neck Annex in Virginia Beach, Va., is a Tier One counter-terrorism and Special Mission Unit with the highest level on the U.S. Special Operations Command spectrum and National Command Authority. All of its operations are classified.
The other such group is 1st Special Forces Operational Detachment-Delta, commonly known as Delta, or Delta Force.
Obama met Wednesday with Navy Vice Adm. William McRaven, a SEAL member who designed and oversaw the bin Laden raid, to thank him personally, CBS News reported.
McRaven is soon to take over leadership of the military's Special Operations Command from Adm. Eric Olson, another SEAL member.
Fort Campbell is also home to the 101st Airborne Division, known as the Screaming Eagles, and the 160th Special Operations Aviation Regiment, known as the Night Stalkers.