Mark Hannah

Opinion contributor

When President Donald Trump announced that he would be withdrawing half of the U.S. troops serving in Afghanistan, the national security establishment was aghast. Afghanistan will become a failed state! The Taliban will expand their power! Chaos and disorder will follow! The critics might be right. The president should follow through anyway.

Aware the war in Afghanistan is unwinnable, Trump nevertheless now dithers. He is being pressured by military leaders who understandably want their sacrifices to have achieved something. And he is selfishly concerned with being blamed if the government in Kabul collapses on his watch.

But letting the Afghanistan War “muddle along” for so many years has been a grievous mistake. Roughly 2,400 U.S. service members and 4,000 American contractors have been killed there, including four just over Thanksgiving. As my old boss, John Kerry, asked a Senate committee in 1971, after returning from that other quagmire in Vietnam, “How do you ask a man to be the last man to die for a mistake?”

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The war in Afghanistan has become a multigenerational exercise in absurdity. Many of the soldiers now fighting and dying were in diapers when the war began. Yet almost two decades and more than a trillion dollars later, the U.S.-backed Afghan government controls only 55 percent of the nation’s territory and 65 percent of its population.

Rather than fading away, the Taliban are stronger than they’ve been at any time since they were ousted when the war began. If our objective is the destruction of the Taliban, the war will be impossible to win militarily.

Don’t take my word for it. The new U.S. general leading our mission in Afghanistan, Scott Miller, conceded to NBC News that “this is not going to be won militarily.”

Instability doesn't always mean insecurity

The decision to invade and occupy Afghanistan was steeped in outdated thinking from an earlier era. In the years leading up to the 9/11 attacks, U.S. foreign policy experts were obsessed with the danger posed by “power vacuums” and “failing states,” and the terrorist breeding grounds they bore. The invasion and occupation of Afghanistan sought to deny al-Qaeda a base for its operations. Yet most of al-Qaeda’s leadership simply fled to Pakistan, and America got bogged down fighting the Taliban, who despite their radical ideology have never had designs on attacking the U.S. mainland. Now, when terrorism is more likely to be homegrown than coordinated from a remote mountain cave, the use of military occupations to disrupt terrorist havens is as antiquated as it is ineffective.

One thing we’ve learned is that American interventionism, however well intentioned, can create more power vacuums than it fills. Such was the case in Iraq and Libya. The threat of “failing states” has been exaggerated. Instability does not necessarily yield insecurity. And some of the biggest challenges to America’s national security come from countries like North Korea, China and Russia, where the control by the central government is all too stable.

In Afghanistan, the Taliban are a fact of life. Instead of trying to defeat or destroy the Taliban, we should define success more in terms of brokering a political settlement — much like the one the Colombian government reached with FARC — that increases the prospects for peace for our Afghan partners after we end our commitment there.

The only thing that can ultimately guarantee the independence and self-determination of the Afghan people is an Afghan government that has its own independence and self-determination. When President Barack Obama announced his timetable for a previous troop drawdown in 2014, Afghan President Ashraf Ghani acknowledged that “deadlines concentrate the mind.” If a more imminent deadline doesn’t prompt the government to rise to the challenge of independent governance, it’s unclear anything will.

The American public is ready for the war to end

Afghanistan has shown signs of confidence. Its national security adviser is meeting with international partners who might help the young government continue to get its footing. One of Ghani’s aides notes that pundits who warned of a doomsday scenario after the 2014 drawdown of U.S. troops were proven wrong, that and “our brave defense and security forces … defended the nation with great valor.”

Even the most strident hawks understand that the war in Afghanistan is unwinnable. Their alternative to withdrawal is to maintain an indefinite troop presence, akin to the permanent stationing of U.S. troops in Germany and Japan after World War II. This is a ludicrous idea. America’s post-World War II occupations guaranteed the security and prosperity of the world’s foremost centers of economic activity, whereas Afghanistan is a desperately poor country with little strategic significance.

The political will to end the war in Afghanistan exists. One recent poll shows that fewer than half of Americans say the initial decision to use military force in Afghanistan was correct. Another new poll finds that a majority of Americans would support a presidential decision to withdraw troops from Afghanistan within a year, while only about one in five would oppose it.

And although some military leaders pressuring the president to stay might feel “pot committed” to the conflict, soldiers and veterans are even more likely than the general public to support a withdrawal of troops from Afghanistan.

Yet few leaders have taken a strong stance toward ending the war. Democrats in particular find themselves in an awkward spot, historically skeptical but inclined to automatically oppose any Trump policy. They should follow the example of Sen. Elizabeth Warren, who displayed political courage by agreeing with the Trump administration’s decision to withdraw troops. Let’s take a break from partisan scorekeeping to, at last, curtail the worst excesses of the so-called War on Terror.

In 1966, in the middle of the Vietnam War, a Vermont senator named George Aiken urged President Lyndon Johnson to “declare victory and get out.” Imagine the financial, geopolitical and human costs that could have been spared if we took his advice then. Let’s take it now.

Mark Hannah is a research fellow at the Eurasia Group Foundation and teaches at New York University. Follow him on Twitter: @ProfessorHannah