Four years after the September 11 attacks, the United States has temporarily put aside their focus on its latest disaster - Hurricane Katrina - to memorials for victims of the hijacked-plane strikes in New York, Washington and Pennsylvania.

Despite this recent disaster, thousands of Americans took their time to remember and praise the memory of more than 2700 lives lost in the Towers fall.

At Ground Zero in New York City, brothers and sisters of the thousands killed in the collapse of the World Trade Center tower read out the victims' names to a quiet crowd of several hundred.

"Again, we are a city that meets in sadness," Mayor Michael Bloomberg said. "We are all linked to one another in our common humanity."

Donald Rumsfeld, Defense Secretary laid a garland at Arlington National Cemetery and delivered a short solemn speech: "I wish we could say ... that this is a time for peaceful remembrance, that we were gathering today to commemorate a danger that had long since past... But we cannot. The enemy, though seriously weakened and continuously under pressure, continues to plot attacks and the danger they pose to the free world is real and present."

In Washington, President Bush marked the fourth anniversary of the Sept. 11 terrorist attacks by observing a moment of silence at 8:46 a.m., the exact minute in 2001 when terrorists smashed the first jetliner into the World Trade Center.