The latest U.S. casualties in America’s interminable war in Afghanistan are three Special Forces soldiers who had been tasked with helping Afghan troops wrest from the Taliban the southeastern city of Ghazni. On Tuesday their convoy set off a roadside bomb. Three days earlier, another American soldier, a 25-year-old Army Ranger from Washington state, was killed in a firefight with al-Qaida militants.

That makes 12 U.S. soldiers killed in Afghanistan this year. Since the war began in 2001, 2,417 U.S. troops have died there. Ninety of them were from Illinois.

So why is America still in Afghanistan? Because the terror groups operating there would have the unfettered ability to again thrive if the U.S. were to withdraw the last of its troops. That answer won’t mollify critics of U.S. policy in Afghanistan during three presidencies. But remember, each of those presidents came to understand the terrible risks a U.S. pullout would create.

We say this acknowledging that there is no end in sight to the longest-running war in U.S. history. Taliban insurgents continue to expand their reach, particularly in the south. Their ambushes and suicide bomb attacks have decimated the ranks of the Afghan military and police. The Islamic State has staked out a presence in the country. And al-Qaida, which had all but disappeared from the battlefield, is back on the scene — as evidenced by the firefight that killed the Army Ranger earlier this month.

It all points to a bleak outlook. But that outlook would quickly grow bleaker if the U.S. withdrew from the country its remaining contingent of about 14,000 troops.

The Afghan government, led by President Ashraf Ghani, is too inept, corrupt and fractured to have any realistic chance of defeating the Taliban on its own.