Most middle school students can tell you why the United States declared war on Japan in December 1941. But how many adults can explain why American troops are in Afghanistan after more than 18 years of war there?

The war has cost billions of dollars and more than 2,300 American lives. It’s dragged on with no end in sight because the goal keeps changing.

The futility of the war was detailed in a long article in the Dec. 8 edition of The Washington Post. Based on confidential government documents obtained by the Post, “senior U.S. officials failed to tell the truth about the war in Afghanistan throughout the 18-year campaign, making rosy pronouncements they knew to be false and hiding unmistakable evidence the war had become unwinnable.”

Generals and others have had to manage a war that has had no clear mission from its beginning to the present day. Goals keep shifting.

The interviews of more than 400 people conducted by Pentagon officials “also highlight the U.S. government’s botched attempts to curtail runaway corruption, build a competent Afghan army and police force, and put a dent in Afghanistan’s thriving opium trade,” the Post reported.

Most people interviewed by the Pentagon assumed their remarks would not become public. They “acknowledged that their warfighting strategies were fatally flawed and that Washington wasted enormous sums of money trying to remake Afghanistan into a modern nation,” according to the Post.

The war has cost the United States nearly $1 trillion. That does not include what the Veterans Administration has spent treating the military personnel who returned home with injuries.

Since 2001, more than 775,000 U.S. troops have deployed to Afghanistan, many repeatedly. Besides the 2,300 who have died there, 20,589 were wounded in action.

At least three of the 2,300 dead were from neighboring Kentucky or Ohio. Spc. Jeremy Raymond Gullett, 22, of Greenup, Kentucky, was killed by a roadside bomb May 7, 2008, in Sabari District. Sgt. Justin B. Allen, 23, of Coal Grove, Ohio, died July 18, 2010, in Zhari of wounds suffered when he was shot by insurgents while conducting combat operations. Matthew Sluss-Tiller, a 1993 Lawrence County (Kentucky) High School graduate, was among three American soldiers killed in a bomb blast Feb. 3 outside a school in Timagera, Pakistan. Three students also were killed in the blast that apparently targeted the soldiers.

President George W. Bush started this war in part to punish the Taliban for its role in 9/11. He did this despite the Soviet Union’s previous failure in conquering and holding Afghanistan. For many people, part of the lesson of the Vietnam War was to avoid becoming entangled in a land war in Asia, let alone start one.

President Barack Obama continued the war effort. So has President Donald Trump, although he is making overtures to the Taliban so the United States can negotiate an acceptable exit.

To echo what Sen. Rand Paul, R-Ky., a longtime opponent of the war, has said, it’s time for Congress to debate whether the United States should continue its war against the Taliban. Before that, though, President Trump could make such a divisive election-year debate moot by bringing our troops home.

Americans have sacrificed enough of their treasure and their lives in a war without clear goals and, it seems, without end. It’s time for President Trump to tell the nation why Americans are still in Afghanistan or else bring them home.