In 1787, Delaware became the first state to ratify the U.S. Constitution.

In 1909, chemist Leo H. Baekeland received a U.S. patent for Bakelite, the first synthetic plastic.

In 1917, during World War I, the United States declared war on Austria-Hungary.

In 1972, America’s last moon mission to date was launched as Apollo 17 blasted off from Cape Canaveral, Fla.

In 1982, convicted murderer Charlie Brooks Jr. became the first U.S. prisoner to be executed by injection, at a prison in Huntsville, Texas.

In 1987, 43 people were killed after a gunman aboard a Pacific Southwest Airlines jetliner in California apparently opened fire on a fellow passenger, the pilots and himself, causing the plane to crash.

Soviet leader Mikhail S. Gorbachev set foot on American soil for the first time, arriving for a Washington summit with President Ronald Reagan.

In 1988, a major earthquake in the Soviet Union devastated northern Armenia; official estimates put the death toll at 25,000.

In 2001, Taliban forces abandoned their last bastion in Afghanistan, fleeing the southern city of Kandahar.

In 2011, Rod Blagojevich, the ousted Illinois governor whose three-year battle against criminal charges became a national spectacle, was sentenced to 14 years in prison. (A pardon from President Donald Trump freed Blagojevich from prison in 2020, after he had served eight years.)

In 2016, President-elect Donald Trump selected retired Marine Gen. John Kelly to head the Department of Homeland Security, Oklahoma Attorney General Scott Pruitt to lead the Environmental Protection Agency, the former CEO of World Wrestling Entertainment, Linda McMahon, to run the Small Business Administration and Iowa Gov. Terry Branstad to be the new U.S. ambassador to China.

In 2017, Democratic Sen. Al Franken said he would resign after a series of sexual harassment allegations; he took a parting shot at President Donald Trump, describing him as “a man who has bragged on tape about his history of sexual assault.” Rep. Trent Franks, R-Ariz., said he would resign, after revealing that he discussed surrogacy with two female staffers.

In 2018, the man who drove his car into counterprotesters at a 2017 white nationalist rally in Virginia was convicted of first-degree murder; a state jury rejected defense arguments that James Alex Fields Jr. acted in self-defense.

Time magazine named Trump its Person of the Year.

In 2020, retired Air Force Brig. Gen. Charles “Chuck” Yeager, the World War II fighter pilot ace and quintessential test pilot who in 1947 became the first person to fly faster than sound, died at 97. A federal judge blocked President Donald U.S. service members and National Park Service officials gathered at Pearl Harbor to remember those killed in the 1941 attack, but elderly survivors stayed home to pay their respects from afar and avoid health risks from the pandemic.