The events of September 11, 2001, set in motion sweeping changes to U.S. intelligence and counterterrorism practices, launched two major wars, and altered Americans’ daily routines. This timeline tra…

In March 2003, U.S. forces invaded Iraq vowing to destroy Iraqi weapons of mass destruction (WMD) and end the dictatorial rule of Saddam Hussein. When WMD intelligence proved illusory and a violent insurgency arose, the war lost public support. Saddam was captured, tried, and hanged and democratic elections were held. In the years since, there have been over 4,700 U.S. and allied troop deaths, and more than one hundred thousand Iraqi civilians have been killed. Meanwhile, questions linger over Iraq's fractious political situation.

Since 1992, negotiations have produced notable accords on climate change, including the Paris Agreement. But leaders have so far failed to slow global warming. Trace the successes and failures of UN climate conferences ahead of COP26.

The quadrennial U.S. presidential nominating conventions are usually dominated by domestic themes. But they have at times been flavored by global economic concerns and national security threats, offe…