This year marks the anniversaries of three miserable wars. It’s the 70th anniversary of the Allied invasion of Italy and the 50th anniversary of the final and most pointless year of the Korean War. 2013 also marks the 12th year that America has been stuck in Afghanistan.

All three of these conflicts were fought in mountains.

Unless you’re a goat, a Gurkha or a Goumier, mountains are bound to make life inconvenient. But for the U.S. military, the exemplar of mechanization, mobility and firepower, mountains are simply awful.

First, there was the Italian campaign targeting the “soft underbelly” of Europe—or so the British promised their American allies. Perhaps it would have been soft had Italy been as flat as Nebraska. Instead, the war became an endless slog up Italy’s mountainous spine, famous for the bitter struggle to capture Monte Cassino, followed by a year spent grinding against the mountainous Gothic Line.

The only nice thing to say about the Italian campaign? The Allies never tried to pull off Churchill’s lunatic plan to land in Yugoslavia and advance through the Balkan mountains into Germany.

Then came the Korean War, which by 1953 had degenerated into bloody and pointless fighting over obscure mountains while both sides bickered over the negotiating table at Pammunjom. The futility of the last year of the conflict was epitomized by the two battles of Pork Chop Hill, which cost the U.S some 350 dead—and the Chinese a lot more—for a piece of real estate that had no strategic value and changed nothing in the eventual cease-fire.

The only nice thing to say about Korea? It didn’t trigger World War III.

And then there’s Afghanistan, which unlike the two previous conflicts, is a counterinsurgency rather than a conventional war. Also unlike Italy and Korea, the Americans have helicopters for mobility. Nonetheless, while the Canadians and U.S. Marine had some success using tanks, Afghanistan is not the most favorable place for mechanized troops.

The only nice thing to say about Afghanistan? You tell me.

10th Mountain Division in Italy in 1945. Wikipedia photo

What is it about these big bumps in the ground that are so difficult for America to fight in? The tactical reason is that mountains restrict mechanized troops to narrow routes, preclude easy maneuver, and allow outnumbered, lightly armed or non-mechanized warriors to hold their own against a more powerful foe.

But it’s more than that. The most striking aspect of the Italian, Korean and Afghan campaigns is that they were all secondary theaters. The terrible slog through the mountainous spine of Italy could easily have been avoided had a few more divisions — and especially amphibious landing craft — been available for amphibious end runs that would have forced the Germans to withdraw from their carefully fortified mountain defenses or be cut off.

But Italy was always a sideshow compared to the invasion of France, for which the Allies hoarded divisions and shipping … and what was left had to be shared with the Pacific theater.

For all the bloodshed in Korea, it was also a sideshow for U.S. planners whose main concern was that diverting too many troops and aircraft from Europe would leave Western Europe exposed to Soviet invasion. Some feared, incorrectly, that the North Korean invasion was merely Stalin’s ruse to divert American attention to Asia instead of Europe.

Between the terrain and the massive Chinese armies that intervened in the conflict, Korea could not be won on the cheap.

For much of the 12-year struggle in Afghanistan, the war was a poor cousin to the fighting in Iraq, which had first priority in resources and political attention after 2003. By the time the U.S. withdrew from Iraq, withdrawal from Afghanistan was also in the works.

This points to an inescapable strategic fact: the most important battlefields, the rich agricultural and industrial areas that nations are most willing to fight over, are usually located on coastlines and plains. Mountainous regions are majestic and beautiful, and often they are perceived as strategic because like Afghanistan, they site astride trade routes, or there are political and emotional attachments, such as between Pakistan and Kashmir.

But they are also areas that tend to be somewhat difficult for their own governments to control, let alone foreign armies. For many an empire, such as the British in India, a mountainous country like Afghanistan was more of an annoyance than a prize.

If there is a lesson here, it is that the U.S. should be careful about fighting a mountain war. And if does fight in the mountains, it needs to commit enough forces to finish the job.

Michael Peck is a contributing editor at Foreign Policy Magazine and writes the War Games blog at Forbes.com. His Twitter is @Mipeck1 , or email him at mikedefense1@gmail.com

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