#9: CHARLESTON CHURCH SHOOTING
A Bible study session at the Emanuel African Methodist Episcopal Church in Charleston, South Carolina, suddenly turned into carnage when a white gunman opened fire, killing nine blacks, including the pastor. The alleged killer's affinity for the Confederate flag sparked debate over the role of Civil War symbols in today's South. In less than a month, the flag was removed from the South Carolina State House grounds.
#8: CLIMATE CHANGE
Negotiators from nearly 200 countries reached a first-of-its kind agreement in Paris on curbing greenhouse gas emissions. Many questions remain over enforcement and implementation of the accord. But elated supporters hailed it as a critical step toward averting the grim scenario of unchecked global warming.
#7: US ELECTION CAMPAIGN
A large and varied field of Republicans launched bids for the presidency, with billionaire Donald Trump moving out to an early lead in the polls and remaining there despite a series of polarizing statements. He helped attract record audiences for the GOP's televised debates. In the Democratic race, Bernie Sanders surprised many with a strong challenge of Hillary Clinton, but she remained the solid front-runner.
#6: TERRORISM WORRIES
Fears about terrorism in the U.S. surged after a married couple in California — described by investigators as radicalized Muslims — carried out the attack in San Bernardino that killed 14 people. The rampage inflamed an already intense debate over whether to accommodate refugees from Syria, and prompted Republican presidential front-runner Donald Trump to call for a ban on Muslims coming to the U.S.
#5: BLACK DEATHS IN ENCOUNTERS WITH POLICE
In Baltimore, riots broke out after the death of Freddie Gray, a black man loaded into a van by police officers. In Chicago, Tulsa and North Charleston, South Carolina, fatal police shootings of black men prompted resignations and criminal charges. The incidents gave fuel to the Black Lives Matter campaign, and prompted several investigations of policing practices.
#4: MASS SHOOTINGS
Throughout the year, mass shootings brought grief to communities across the U.S. and deepened frustration over the failure to curtail them. There were 14 victims in San Bernardino. Nine blacks were killed by a white gunman at a Charleston, South Carolina, church; a professor and eight students died at an Oregon community college. In Chattanooga, four Marines and a sailor were killed by a Kuwaiti-born engineer; three people, including a policeman, were shot dead at a Planned Parenthood clinic in Colorado.
#3: PARIS ATTACKS
The first attack came just a week into the new year. Two brothers who called themselves members of al-Qaida barged into the offices of the satiric newspaper Charlie Hebdo, and later attacked a Jewish market, gunning down 17 people in all. Nov. 13 brought a far deadlier onslaught: Eight Islamic State militants killed 130 people in coordinated assaults around Paris. Targets included restaurants, bars and an indoor rock concert.
#2: GAY MARRIAGE
Fifteen years after Vermont pioneered civil unions for same-sex couples, the Supreme Court issued a ruling in June enabling them to marry in all 50 states. Gay-rights activists heralded it as their movement's biggest breakthrough, but there were flashes of disapproval. A county clerk in Kentucky, Kim Davis, spent a few days in jail after refusing to issue marriage licenses to gay couples in her jurisdiction.
AND THE "WINNER" IS ...
#1: ISLAMIC STATE
A multinational coalition intensified ground and air attacks against Islamic State militants in Iraq and Syria, including expanded roles for Western European countries worried about IS-backed terrorism. For its part, IS sought to demonstrate an expansive reach by its operatives and supporters, claiming to have carried out or inspired the bombing of a Russian airliner, attacks in Beirut and Paris, and the deadly shooting in San Bernardino, California.
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