Welcome to the decade of the 2010s, a period of environmental disaster, unthinkable violence and protests fueled by social media.

More than a million Americans assembled to greet the “twenty-tens” at midnight in New York’s Times Square despite freezing rain and snow.

Those celebrating more comfortably at home could join legendary Dick Clark for his “New Year’s Rockin’ Eve” program on ABC. 2010s performers included a 15-year-old Justin Bieber, The Black Eyed Peas, the rock band Doughtry, “Wizards of Waverly Place” star Selena Gomez and headliner Jennifer Lopez, already a veteran entertainer.

But little did the New Year’s performers or the festive crowds know what lay ahead. The decade would be marked by seismic changes in the political landscape and scarred by a spate of school shootings, natural disasters and terrorist attacks, leaving many Americans eager to say goodbye — and ultimately good riddance — to the 2010s.

An explosion rocked the waters off the Gulf Coast on Tuesday, April 20, 2010.

The catastrophe on the Deepwater Horizon oil platform, about 42 miles southeast of Louisiana, killed 11 individuals and spewed millions of barrels of oil into the Gulf of Mexico over 87 days.

The disaster prompted a robust environmental response as government agencies and others worked through 2013 to mitigate the damage. Oil reached the shorelines of Texas, Alabama, Mississippi, Louisiana and Florida and devastated the Gulf Coast economy, which relies on fishing and tourism.

Not since the 1989 Exxon Valdez disaster in Alaska had a marine oil spill drawn so much public attention in the U.S. The news was filled with images of oil-soaked shorelines, cleanup crews and afflicted wildlife.

The National Oceanic and Atmospheric Administration estimates the disaster resulted in the deaths of more than 105,000 birds, 167,000 sea turtles and “up to a 51-percent decrease in dolphins in Louisiana’s Barataria Bay.” The spill also devastated fish populations, damaged fragile deep-sea coral and killed as many as 8.3 billion oysters, according to NOAA.

A 2011 report to Congress laid the blame on faulty cement in the well, a result of cost-cutting by BP and its partners, which had chartered the well. Among other penalties, the company was ordered to pay $20.8 billion, the largest environmental damage settlement in U.S. history, on April 4, 2016.

Superstorm Sandy clobbered the Caribbean in October 2012. By the time it hit the U.S. mainland near Atlantic City, N.J., on Oct. 29, it had been downgraded to a tropical storm.

Yet Sandy’s heavy rains, high tides and a sprawling footprint of more than 1,000 miles in diameter produced a record-breaking storm surge that ravaged many coastal communities. The storm sent nearly 14 feet into New York City’s Battery Park and flooded an incredible 51 square miles of the city, according to a report from NYC.gov.

Overall, the storm destroyed about 650,000 homes, caused the deaths of more than 70 people and resulted in damages in excess of $70 billion in the U.S. alone, the second-most costly hurricane in the nation’s history at the time.

The record didn’t stand for long. In fact, three of the top 10 costliest storms in history would hit the U.S. in 2017 alone, according to the National Hurricane Center: Category 4 storms Irma, causing $50 billion in damage and at least 84 deaths, primarily in Florida; Maria, causing $90 billion in damage and nearly 3,000 deaths in Puerto Rico; and Harvey, the second-costliest hurricane on record, causing $125 billion in damage and 106 deaths in Texas and Louisiana.

Falling short of the vision of its organizers, the Occupy Wall Street movement flashed onto the televisions and into the newspapers of America for a brief two months in the fall of 2011.

Characterized by some as a “populist movement,” around 300 protesters gathered Sept. 17 in Zuccotti Park in lower Manhattan to draw attention to income inequality, with a focus on the U.S. financial sector.

The group, comprised chiefly of students and college graduates, coordinated its efforts using social media, demonstrating the growing power of the platform as an organizing tool.

As the outdoor “camp-in” continued and police made arrests, the movement drew the attention of national media, garnering an advertising equivalent of nearly $1 million a night at its peak, according to Nielsen research.

Mayor Michael Bloomberg ordered New York City police to evict remaining protesters Nov. 15, citing concerns about mounting health and fire safety hazards to the protesters and the surrounding community. Subsequent efforts to reignite the protests were quickly suppressed.

While the Occupy movement was short-lived, it was an early example of the public activism that would come to be a hallmark of the 2010s, setting a template for social media-fueled organizing around issues such as sexual harassment (#MeToo) and police violence (#BlackLivesMatter).

Their names became part of America’s lexicon: Trayvon Martin, 17, shot by a neighborhood watch volunteer in Sanford, Fla., Feb. 26, 2012; Eric Garner, 43, who died July 17, 2014, as a result of a chokehold by a New York City police officer; and Michael Brown, 18, shot during a confrontation with a police officer in Ferguson, Mo., on Aug. 9, 2014.

The deaths of these unarmed African American men and others, paired with ongoing concerns about a lack of accountability for those responsible, sparked widespread outrage and activism.

Spreading like lightning on social media, the phrase “Black Lives Matter” became a rallying cry for the movement. It was soon adopted as the name of a network of advocates seeking to fight systemic racism.

Thousands of citizens took to the streets following the death of Michael Brown, chanting “Black Lives Matter” and “Hands up, don't shoot.” While many protests were peaceful, others spawned social disorder and violent confrontations with police.

With its memorable hashtag and outspoken grassroots members, the movement went on to have a profound impact on the political rhetoric of the 2016 election. BLM activists confronted candidates such as Sen. Bernie Sanders and Florida Gov. Jeb Bush, and staged protests at Republican events.

The movement prompted financial and institutional responses from corporate America. Companies such as Google, Ben & Jerry's and Twitter were among the early donors to the cause. Organizations also responded to public pressure by promoting social justice initiatives and diversity-infused practices within their own operations, one of the legacies of 2010s BLM activism.

The 2010s shook Americans’ sense of safety as violence erupted not only on the streets but also in schools, churches, synagogues and public events.

As the nation prepared for the holidays in December 2012, a gunman opened fire in Sandy Hook Elementary School in Newtown, Conn., killing 20 first graders and six staff members. Those children would have graduated from high school in June 2024.

Just four months later, two pressure-cooker bombs exploded near the finish line of the Boston Marathon in a terrorist attack on April 15, 2013. Shrapnel and the force of the blast killed three, including an 8-year-old boy, and injured at least 260 others. Victims suffered broken bones and severed limbs, flesh wounds and damage to internal organs.

Across the country, a gunman shot more than 1,000 rounds at Las Vegas concertgoers from a 32nd-floor hotel room on Oct. 1, 2017. The 10-minute shooting spree — the deadliest in U.S. history — left 60 dead and more than 400 wounded.

The next spring, 14 students and three staff members were killed in a mass shooting at the Marjory Stoneman Douglas High School near Miami on Feb. 14, 2018.

In the Squirrel Hill neighborhood of Pittsburgh, 11 individuals were killed and six injured in an Oct. 27, 2018, shooting at the Tree of Life synagogue. Three of the dead were Holocaust survivors.

Five of the 10 deadliest mass shootings in the U.S. took place in the 2010s, according to the Gun Violence Archive.

After years of advocacy, public debate and legal battles, the 2010s brought major victories in the fight for LGBT rights.

At the dawn of the decade, polling by the Pew Research Center showed a plurality (48% vs. 42%) of Americans opposed same-sex marriage.

But by 2011, the tide was already turning, with 46% of Americans in favor and 44% opposed.

As state legislatures, courts and popular votes approved same-sex marriage or civil union protections through the early 2010s — a total of 36 states by 2015, including Pennsylvania in May 2014 — the stage was set for a showdown in the Supreme Court.

The landmark Obergefell v. Hodges decision, issued June 26, 2015, established the constitutional right of same-sex couples to marry. The decision made same-sex marriages legal in all 50 states and U.S. territories.

While there was much to celebrate for LGBT-rights advocates, the legal victory was only part of the battle.

Just one year later, on June 11, 2016, a gunman opened fire inside Pulse, a gay nightclub in Orlando, Fla., killing 49 people and wounding more than 50 others — the second deadliest mass shooting in U.S. history.

Though the perpetrator said he was acting in response to America’s military role in the Middle East, the attack was considered a crisis for the LGBT community, highlighting continuing concerns about LGBT safety and discrimination.

The brainchild of Lin-Manuel Miranda, the musical “Hamilton” took Broadway by storm in the 2010s, winning 11 Tony Awards including Best Musical, the 2016 Pulitzer Prize for Drama and a Grammy Award for best musical theater album.

After opening Jan. 20, 2015, at the off-Broadway Public theater, the show moved to the Richard Rodgers Theatre in July.

With audiences paying hundreds of dollars per ticket at sold-out performances, the show repeatedly set earnings records, breaking the $4 million one-week earnings mark in December 2018, nearly four years after its opening, according to the Broadway News.

Inspired by the 2004 book by Ron Chernow, “Hamilton” retells story of the American Revolution using a diverse cast, innovative storytelling and a musical score that seems to defy description. Writing for the New York Theater Guide, arts journalist Kiep Tran gave it a try, describing the score as “an anachronistic mix of hip-hop, rap, pop, jazz and Broadway showtunes.”

Called a “global musical juggernaut” by the Los Angeles Times, the show ranks as the fourth highest grossing Broadway musical of all time, earning more than $941 million as of 2024, according to the Broadway League.

For more on both the musical and its subject, see our profile of Alexander Hamilton in this edition.

Step aside, Tom Brady and Floyd Mayweather Jr., for the dominant athlete of the 2010s: American gymnast Simone Biles.

“My journey to the 2016 Olympics started on a day care field trip,” Biles writes on her website, calling that journey “miraculous.” The Columbus, Ohio, native spent time in foster care before being adopted by her grandparents.

But similarly miraculous to the typical observer were Biles’ explosive vaults, dizzying flips and incredible power.

Only five years after her first national competition, a 19-year-old Biles was winning gold at the 2016 Olympics in Rio de Janeiro: individual gold medals in the vault, floor and all-around categories; a bronze medal for balance beam; and a gold medal as a member of the U.S. gymnastics team.

By the end of the decade, Biles was the most-decorated gymnast — man or woman — in history, with a total of five Olympic and 25 World Championship medals, including five all-around World titles. 2019 didn’t mark the end; her list of accomplishments would continue to grow in the 2020s.

Gold medals are one thing. But a gold escalator is quite another.

It was a gold escalator on which Donald Trump descended June 16, 2015, into the lobby of Trump Tower in New York City to announce his run for president of the United States. The escalator ride would be described in the media as “surreal” and even “quixotic.”

Vowing to “build a wall” and “drain the swamp,” the real estate mogul entered the race among a crowded field of Republican candidates including Florida Gov. Jeb Bush, former Pennsylvania Sen. Rick Santorum and the Pennsylvania-born governor of Ohio, John Kasich.

Tapping into the frustration that many voters felt regarding immigration and political ineffectiveness inside the beltway, Trump’s brash, often vitriolic style carried him to a 304-227 Electoral College victory over his Democratic opponent, former Secretary of State Hillary Rodham Clinton.

The Trump administration compiled a mixed record in its first three years. On the economic front, deregulation and 2017 tax reforms were credited by many for boosting economic growth and employment. U.S. Bureau of Labor Statistics data show unemployment rates reached historic lows for American Americans (5.3% in August and September 2019), Latinos (3.9% in November 2019) and women (3.4% in October 2019, the lowest rate for women since the 1950s).

Other successes included support for Historically Black Colleges and Universities, criminal justice reform and a “record-low” number of apprehensions at the southern border, according to U.S. News and World Report and data from the U.S. Customs and Border Protection agency.

Yet the administration was tarnished by controversy. A high turnover rate among officials and cabinet members suggested discontent and disarray within the Trump White House. Many viewed the president’s response to an August 2017 clash between white supremacists and counterprotesters in Charlottesville, Va., as divisive and exacerbating to racial tensions. Trump’s use of social media and his criticism of traditional media as “fake news” upended traditional political practices.

Trump’s term in office was also marred by ongoing investigations into Russian interference in the 2016 election. Congress later voted to impeach the president following accusations that the president had abused his power in asking Ukrainian President Volodymr Zelensky to investigate former Vice President Joe Biden and his son, Hunter Biden. The president would be acquitted of those charges in February 2020.

While many were happy to say goodbye to the 2010s, the decade ushered in profound legal, social and technological transformations, setting the stage for ongoing change in the 2020s. But the onset of COVID would disrupt expectations in ways no one could have predicted.

Katrina Jesick Quinn is a professor at Slippery Rock University. She is an editor of From the Arctic to the Orient: Adventure Journalism in the Gilded Age (McFarland) and The Civil War Soldier and the Press (Routledge).