[Updated January 28, 2019]

Even the most dedicated news junkies can find it difficult to keep up on the war in Afghanistan, now in its 18th year.

This guide is for those who could use a refresher on the conflict, in which more than 2,400 Americans have died. At least 62,000 Afghan soldiers and police officers have been killed since the war began, in 2001, and more than 24,000 civilians have died in the past decade.

Now, after nine years of intermittent peace efforts, American and Taliban officials have agreed in principle to the framework of a deal that could lead to a full pullout of American troops in return for a series of concessions from the Taliban, the chief United States negotiator said on Monday.

Why is the United States military still there?

President George W. Bush launched the first missiles in October 2001, about a month after the Sept. 11 attacks. The goals were to destroy Al Qaeda and the Taliban government that protected it, and to ensure the country wouldn’t be a safe haven for terrorists.