When many of us worked hard in 2012 for “four more years,” we were talking about Barack Obama’s presidency, not a continued significant presence of American troops in Afghanistan. Gen. Joseph Dunford, the commander of U.S. forces there, appears concerned that the president might do the sensible thing and withdraw American troops from that country sometime next year — 11 years or so after we first invaded for the specific purpose of getting Osama bin Laden.

Gen. Dunford has a difficult balancing act in his effort to prolong America’s military engagement there. On the one hand, he understands that it’s important for his purpose to portray the Afghan government as competent, and its military as a courageous fighting force, lest Americans come to the conclusion that propping up that regime is a hopeless task — or, at the very best, an endless one. On the other hand, he does not want the Afghans to appear fully self-sufficient, since then the justification for tens of billions more American dollars being spent there would disappear.

Most relevantly, he acknowledges that al-Qaida — as distinguished from the Taliban — has been rendered largely ineffective. In a New York Times interview he requested, he said that there are only about 75 al-Qaida terrorists left in Afghanistan, and even these are very much on the defensive. But, he warns, if America withdraws its military, and the Afghan government has to deal with this on its own, al-Qaida may spring back to life.

Let’s be very clear about what this means. Afghanistan is not confronted with an outside enemy. The question is whether or not the Afghan government can survive the assault from its internal enemy — the Taliban. At this point it is important to remember that when George W. Bush became president in 2001, removing the Taliban from power in Afghanistan was in no way part of his agenda. Remember, too, that the Taliban, for intra-Muslim religious reasons, is hostile to its next-door neighbor, Iran, and vice versa. President Bush was perfectly willing to coexist with a Taliban regime in power in Afghanistan until bin Laden used that country as a haven from which to commit mass murder.

I would very much prefer an Afghanistan without the Taliban in power. I would also prefer to see Robert Mugabe removed from power in Zimbabwe. The leaders of several of the “stans” in the former Soviet Union are also wholly undesirable rulers of their countries from any standpoint of moral decency. Diplomatic disapproval, sanctions, opposing loans for these countries from international financial institutions — these are all reasonable means of expressing our displeasure. Using the American military to install and indefinitely prop up new rulers in any of these countries is not.

As to Afghanistan, after 11 years, after hundreds of billions of taxpayer dollars, thousands of American lives lost, and many, many more grievously wounded, the time has come to recognize that our military will never be able to succeed in creating a stable, honest Afghan government that’s respectful of human rights. Gen. Dunford’s request is that we commit thousands of the best armed combat soldiers in the world, and tens of billions of dollars more to try to prop up the Karzai government, which, by the general’s acknowledgement, could not survive without us.

Conservatives, when they are ideologically opposed to public programs to alleviate poverty, or provide public transportation, or combat environmental ills, often scoff that we who support these approaches are “only throwing money at a problem.” Of course, in many cases, money is an essential element in bringing about social improvement. But in the case of Afghanistan, their argument has a point: The last 11 years demonstrate that we cannot throw enough money and troops at the Karzai regime — or the successor he will almost certainly hand pick — to accomplish any purpose relevant either to our national security, or to the vindication of our moral values.

The next time Gen. Dunford urges Obama to stay in Afghanistan, he should answer three questions: How many troops do you think we should keep in Afghanistan? For how long? And for how much money?

Secretary of Defense Chuck Hagel laments that reducing military spending to the level Congress set in the sequestration bill will require some very tough choices. Why not, then, make an easy one — to stop throwing tens of billions at trying to transform Afghan society?

Barney Frank is a retired congressman and author of landmark legislation. He divides his time between Maine and Massachusetts. You can follow him on Twitter: