Every American -- and many others around the world -- remembers where he or she was when the first news came in that a plane had been flown into the World Trade Center. The morning of Sept. 11, 2001, would end with two hijacked airliners flown into each of the WTC towers, another plane flown into the Pentagon, and a fourth plane crashing into the ground in Pennsylvania after passengers stormed the cockpit. The death toll would be nearly 3,000 in the worst terrorist attack in U.S. history, events that made al-Qaida and Osama bin Laden household names despite previous attacks by the terror outfit on U.S. installations. While most were horrified by the carnage, footage around the globe notably captured some cheering at the attacks on America.The intelligence that led to the March 2003 U.S.-led invasion of Iraq remains a story and controversy in and of itself, but the invasion changed the decade -- and history -- in a way that its predecessor, the 1990-91 Gulf War, didn&#39;t touch. Saddam Hussein, the brutal dictator of Iraq since 1979, was successfully ousted from power; his two sons, Uday and Qusay, were killed in fighting with coalition troops; and Saddam himself was found hiding in a hole on Dec. 14, 2003. Tried for crimes against humanity, Saddam was hanged on Dec. 30, 2006, marking an official end to the Baathist regime. On June 29, 2009, U.S. forces withdrew from Baghdad, but the situation is still unstable and is likely to make news into the next decade.The wave struck on Dec. 26, 2004, with a catastrophic force usually confined to apocalyptic action flicks. The second-largest earthquake ever recorded, with at least 9.1 magnitude, ripped the floor of the Indian Ocean west of Indonesia, slamming 11 countries -- as far away as South Africa -- with waves up to 100 feet high. The tsunami claimed victims in third-world villages and plush tourist resorts, and nearly 230,000 people were killed or missing and presumed dead. The devastation prompted a massive global humanitarian response, with more than $7 billion donated to the affected regions. The disaster also prompted the creation of the Indian Ocean Tsunami Warning System.The worst economic downturn since the Great Depression -- which economists peg as beginning in the U.S. in December 2007, and wasn&#39;t expected to modestly recover until 2010 -- showed that globalization means no country would be immune from effects of the rash of foreclosures, rising unemployment rates, controversial bank bailouts and weak GDP. As countries suffered the ripple effects of downturns in trading partners and neighbors, world leaders grappled with how to counter the economic crisis in a unified manner. British Prime Minister Gordon Brown unsuccessfully tried to push his &#34;global new deal&#34; in response, but most leaders agreed in principle that better regulatory oversight was needed to prevent another similar crisis in the future.The Darfur conflict began in 2003 in western Sudan, when rebel groups began fighting the government and its allied Arabic-speaking Janjaweed militia. The result was mass killings of civilians and mass displacements resulting in a humanitarian crisis of epic proportions. But Darfur also became a celebu-cause, attracting advocates such as George Clooney, and roused a too-familiar argument at the United Nations about what constitutes genocide and what necessitates U.N. action. In 2004, however, U.S. President George W. Bush did declare the conflict -- which took an estimated 300,000 lives between 2003-05 and displaced two million -- a genocide. The war in Darfur touched off the civil war in Chad in 2005.After years of declining health, Pope John Paul II -- who had led the world&#39;s one billion Roman Catholics since 1978 -- died at the Vatican on April 2, 2005. This prompted what has been called the largest Christian pilgrimage ever, with four million mourners descending on Rome for the funeral, which also drew the most heads of state in history: four kings, five queens, 70 presidents and prime ministers, 14 heads of other religions. After John Paul was laid to rest, the world watched in anticipation as the conclave elected Cardinal Joseph Ratzinger on April 19, 2005. The elderly, conservative Ratzinger took the name Pope Benedict XVI, and the new German pontiff meant that the position would not go back to an Italian.The Gulf Coast knew it was coming. As the sixth strongest hurricane in Atlantic history came hurtling toward New Orleans, mass evacuations were urged. Katrina roared onshore as a Category 3 storm on Aug. 29, 2005, spreading destruction from Texas to Florida. But it was the subsequent failure of the levees in New Orleans that wreaked the worst humanitarian disaster, covering 80 percent of the city in stagnant floodwaters for weeks. Adding to the crisis was the weak government response from the Federal Emergency Management Agency, with the Coast Guard taking the lead on plucking stranded residents from rooftops. Katrina claimed 1,836 lives, mainly in Louisiana and Mississippi, with 705 people categorized as missing.The Oct. 7, 2001, U.S.-UK invasion of Afghanistan toppled the brutal Taliban regime, but was the most conventional action in a war that has rewritten the rules on conflict. The global war on terror was sparked by the Sept. 11, 2001, al-Qaida attacks on U.S. soil, though Osama bin Laden&#39;s group had previously struck U.S. targets -- embassies in Kenya and Tanzania and the USS Cole off Yemen. In the years since, various countries&#39; commitments to the battle have ebbed and the efforts to root out terrorist plots, cells and financing have given rise to controversies about civil liberties and religious profiling. Commitment to fighting terrorism has also become a key point of political campaigns around the globe.The highest-profile celebrity story of the decade is easy: the death of Michael Jackson at age 50 on June 25, 2009. The sudden death of the pop star -- and for years, a controversial figure mired in sexual abuse allegations and other scandals -- was attributed to a cocktail of drugs that stopped his heart, prompting an investigation of Jackson&#39;s personal physician. A star-studded memorial service was held for Jackson at the Staples Center in Los Angeles, including his three children who had been famously sheltered from media during the singer&#39;s lifetime. The story, which garnered massive worldwide attention, also showed the shift in the media paradigm, with pop-culture website TMZ breaking the story that Jackson had died first.This is the story of the decade that&#39;s sure to make even more headlines in the next decade. Iran has steadfastly claimed that its nuclear program is for peaceful energy purposes, but various intelligence sources have put the belligerent Islamic Republic within dangerous reach of developing a nuclear weapon. The trash-talking regime, which continually rails against the West and Israel, also hasn&#39;t left many with doubt about motivation for wanting a nuclear weapon or Tehran&#39;s willingness to use it. The issue has been tied up in various negotiation processes, United Nations deliberations, IAEA probes and sanctions debates, which many have observed is buying Iran time to press forward with its program, whatever the intentions.