Answer: 1970s:
Watergate scandal (1972-1974): The break-in at the Democratic National Committee headquarters and subsequent cover-up led to the resignation of President Richard Nixon.
End of the Vietnam War (1975): The United States withdrew its troops from Vietnam, ending its involvement in the Vietnam War.
Energy crisis (1973-1974): OPEC oil embargo resulted in fuel shortages and high energy prices in the United States.
Roe v. Wade (1973): The Supreme Court decision legalized abortion in the United States.
Iran hostage crisis (1979-1981): American embassy in Iran was seized, and 52 Americans were held hostage for 444 days.
1980s:
Ronald Reagan presidency (1981-1989): Reagan implemented conservative policies known as Reaganomics and played a role in ending the Cold War.
Iran-Contra affair (1985-1987): A political scandal in which the Reagan administration secretly sold arms to Iran and used the proceeds to fund anti-Sandinista rebels in Nicaragua.
Fall of the Berlin Wall (1989): The wall separating East and West Berlin was torn down, symbolizing the end of the Cold War.
HIV/AIDS epidemic: The 1980s saw the emergence and spread of the HIV/AIDS virus, which had a significant impact on public health and led to activism and increased awareness.
Challenger space shuttle disaster (1986): The space shuttle Challenger exploded shortly after launch, resulting in the deaths of all seven crew members.
1990s:
Gulf War (1990-1991): A military conflict between a coalition led by the United States and Iraq following Iraq's invasion of Kuwait.
Fall of the Soviet Union (1991): The Soviet Union dissolved, marking the end of the Cold War and the emergence of new independent states.
Bill Clinton presidency (1993-2001): Clinton oversaw economic prosperity and became the second president in U.S. history to be impeached.
O.J. Simpson trial (1995): The trial of former football player O.J. Simpson for the murder of his ex-wife Nicole Brown Simpson and her friend Ronald Goldman gained significant media attention.
Columbine High School shooting (1999): A tragic school shooting in Colorado that led to increased discussions about gun control and school safety.
2000s:
September 11 attacks (2001): Terrorist attacks carried out by Al-Qaeda hijackers on the World Trade Center in New York City and the Pentagon in Washington, D.C., resulting in the deaths of nearly 3,000 people.
War on Terror: The United States, under President George W. Bush, launched military campaigns in Afghanistan (2001) and Iraq (2003) as part of the response to the September 11 attacks.
Hurricane Katrina (2005): A devastating hurricane that struck the Gulf Coast, particularly New Orleans, causing widespread destruction and loss of life.
Great Recession (2007-2009): A global economic downturn triggered by the collapse of the housing market and financial crisis, resulting in significant job losses and economic instability.
Election of Barack Obama (2008): Obama became the first African American president in U.S. history, symbolizing a significant milestone in the country's history.
Step-by-step explanation: