International combat operations in Afghanistan, now involving U.S. troops almost exclusively, are to come to a formal end at the close of 2014.

The war has lasted roughly 13 years — by far America’s longest-running war.

The families of the returning troops will be happy to see them come home. The rest of the country seems largely to have forgotten about them.

Why is that?

How can that be?

We still have 68,000 troops there, battling the Taliban and struggling to train the Afghan army.

Moreover, the Obama administration is said to want to keep 10,000 troops there after 2014 to continue training Afghan regulars, to conduct anti-terrorist measures, and to keep the country from falling into the hands of the Taliban.

Whether the U.S. troops stay depends on signing a treaty with Afghanistan’s mercurial president, Hamid Karzai. He is not the most reliable ally, to put it mildly. And he is also term limited — a lame duck.

None of this is getting much attention from Congress. And the war in Afghanistan is getting zero attention from the public. Some 68,000 troops and our longest war have become invisible. That is really unconscionable.

How can it be?

Here’s how:

A tiny fragment of the country — less than 0.5 percent — fights our wars, that’s how. And they tend to be the children of the poor and the struggling working class.

It’s not right.

The defense of the country should be widely — indeed, universally — shared, first as matter of justice and second as a democratic check on a professional military.

You can be very sure that if there were a draft, this war would not be invisible.

Our fighting men and women would not be invisible.

And some of those men and women would not be on their third, fourth, and fifth tours of duty.

There should be a draft.

We need universal service for all Americans: two years in the military or three in non-military national service.

Just as there should be universal national health insurance, there should be universal national military service.

The only thing worse than making the war invisible is making our service personnel invisible, when many of them have made extraordinary sacrifice and borne far more than their share of the defense burden.

Only a few of our young men and women are charged with defense of the nation. This is wrong. It is the greatest injustice now before the country. Yet this injustice, like the war and those who fight it, is invisible.

Again, there is only one word: Unconscionable.