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Obama: 'We mean what we say'

President Obama visited several landmark sites related to the Sept. 11, 2001 terrorist attacks in New York City before he participated in a wreath-laying ceremony at Ground Zero.

The president was accompanied by former New York City Mayor Rudy Giuliani at his first stop, the "Pride of Midtown" firehouse, which, according to the White House, lost 15 men on 9/11 -- more than any other New York firehouse.

In his remarks, the president did not mention the killing of Osama bin Laden directly, but told the assembled firefighters, "What happened on Sunday" sent a message around the world that "when we say we will never forget, we mean what we say."

He seemed to try to discourage any perception that he was scoring political points over the mission, saying, "Our commitment to making sure that justice is done is something that transcended politics, transcended party; it didn’t matter which administration was in; it didn’t matter who was in charge; we were going to make sure that the perpetrators of that horrible act -- that they received justice."

The president made similar remarks when he visited a second off-schedule location, the First Precinct Police Station in Lower Manhattan, which was the first precinct to respond to the 9/11 attack.

The president said that the bin Laden killing, which he again referred to as, "What we did on Sunday," is connected to what the police officers in New York City and around the world do every day -- acts of bravery, without a lot of fanfare, to keeping Americans safe.

After the stop at the precinct, President Obama continued on to Memorial Plaza at the September 11th Memorial and Museum, where he placed a wreath at the Survivor Tree, which has its own lore, according to the White House. It was originally planted at the World Trade Center in the 1970s and sustained significant damage during the attack. It was recovered from rubble and brought to a nursery. When it was admitted to the nursery in November 2001, the tree stood eight-feet high. Now, back at the Memorial site, it is 30-feet tall.

The president also visited with families of 9/11 victims at a private stop after the wreath-laying.