On August 7, 1782, in Newburgh, New York, General George Washington, the commander in chief of the Continental Army, creates the “Badge for Military Merit,” a decoration consisting of a purple, heart-shaped piece of silk, edged with a narrow binding of silver, with the word Merit stitched across the face in silver. It would come to be widely known as the Purple Heart.

On August 7, 1942, the U.S. 1st Marine Division begins Operation Watchtower, the first U.S. offensive of the war, by landing on Guadalcanal, one of the Solomon Islands.

Seven army ammunition trucks explode in Cali, Colombia, killing more than 1,000 people and injuring thousands more on August 7, 1956. The cause of the explosions remains a mystery.

From the Atlantic Missile Range in Cape Canaveral, Florida, the U.S. unmanned spacecraft Explorer 6 is launched into an orbit around the earth. The spacecraft, commonly known as the “Paddlewheel” satellite, features a photocell scanner that transmitted a crude picture of the earth’s surface and cloud cover from a distance of 17,000 miles. The photo, received in Hawaii, takes nearly 40 minutes to transmit.

High above the early-morning traffic in Lower Manhattan, a French street performer steps off the roof of the south tower of the World Trade Center on August 7, 1974. Clad in black and carrying a long pole for balance, Philippe Petit begins the most famous high-wire walk in history, calmly traversing the space between the Twin Towers at a height of 1,350 feet.

On August 7, 1990, President George Herbert Walker Bush orders the organization of Operation Desert Shield in response to Iraq’s invasion of Kuwait on August 2. The order prepared American troops to become part of an international coalition in the war against Iraq that would be launched as Operation Desert Storm in January 1991. To support Operation Desert Shield, Bush authorized a dramatic increase in U.S. troops and resources in the Persian Gulf.

At 10:30 a.m. local time, a massive truck bomb explodes outside the U.S. embassy in Nairobi, Kenya. Minutes later, another truck bomb detonated outside the U.S. embassy in Dar es Salaam, the capital of neighboring Tanzania. The dual terrorist attacks killed 224 people, including 12 Americans, and wounded more than 4,500. The United States accused Saudi exile Osama bin Laden, a proponent of international terrorism against America, of masterminding the bombings. On August 20, President Bill Clinton ordered cruise missiles launched against bin Laden’s terrorist training camps in Afghanistan and against a pharmaceutical plant in Sudan, where bin Laden allegedly made or distributed chemical weapons.