I'd say the quickest way to sum up the decade is in photos. Unfortunately, LIFE already beat me to that. There's obviously way more where these photos came from (four whole years, for that matter). You can see the whole decade here -- and leave your favorite photographic moments in the comment section!
The world witnessed imperfections to the U.S. electoral system when the 2000 presidential contest between Texas Gov. George W. Bush and Vice President Al Gore came down to a series of holes punched into antiquated mechanical ballots in a couple of counties in Fla.
Robert King/Getty Images/Courtesy of 'Life'
The ruins of what was once the World Trade Center towers became known as Ground Zero — a smoldering pit in America's financial center — with the terrorist attacks on Sept. 11, 2001.
Alex Fuchs/AFP/Getty Images/Courtesy of 'Life'
On May 1, 2003, President George W. Bush declared the end of major combat operations in Iraq, but the words that spoke loudest were on a banner behind him, prematurely announcing, "Mission Accomplished."
Stephen Jaffe/AFP/Getty Images/Courtesy of 'Life'
Perhaps one of the most memorable sporting events was the 2004 Super Bowl in 2004. Actually — not for the game itself, but the halftime show, in which Justin Timberlake tore off part of Janet Jackson's top.
Donald Miralle/Getty Images/Courtesy of 'Life'
The story of threatened wildlife is not news. But this photograph and many others in recent years have made it clear exactly what is at stake.
Brent Stirton/Edit by Getty Images/Courtesy of 'Life'
The Merapi volcano — Indonesia's most active — erupted in late 2010. By mid-November, the eruptions had forced the evacuation of 350,000 people, according to Life.