As U.S. forces withdraw from parts of Afghanistan, the Taliban is making gains in several areas of the country. The Afghan police and army are slowly giving way, despite the United States spending 13 years and tens of billions of dollars training those forces. When the United States completes its withdrawal from ground combat at the end of this year, this unfavorable trend will undoubtedly accelerate – that is, if the Afghan security forces don’t collapse altogether, as did similarly U.S. trained Iraqi forces in that country. Thus, in the longest war in American history, the U.S. military has failed to pacify Afghanistan – as had the mighty British Empire three times in the 19th and early 20th centuries and the Soviet superpower more recently in the 1980s. In fact, an outside force has not pacified Afghanistan since Cyrus the Great of Persia did it in ancient times.

Why did the United States have the hubris to think it could succeed in taming Afghanistan, when all of these other strenuous efforts had failed? Because many in the American foreign policy elite, media, and citizenry believe in "American exceptionalism." As propounded by politicians of both parties – for example, Hillary Clinton and Madeleine Albright in the Democratic Party and people such as John McCain and his sidekick Lindsay Graham in the Republican Party – America is the "indispensable nation" to a world that cannot do without its solving most major problems using military power. Yet despite the current public fawning over military personnel and veterans of American wars, the U.S. military has been fairly incompetent in most major engagements since World War II that required significant ground forces – with only Desert Storm in 1991 being an unvarnished success in recent years. The U.S. armed forces are probably more powerful than any other military in world history, both absolutely and relative to other countries, yet their battlefield performance has not been that great, especially against irregular guerrilla forces in the developing world.

In the post-World War II era, the U.S. military managed to fight the then-poor nation of China to only a draw in the Korean War (1950-1953); lost the Vietnam War (1965-1973) to rag tag Viet Cong guerrillas and North Vietnamese; and made the same mistakes of Vietnam in Iraq and Afghanistan – initially using excessive firepower and alienating the population, the allegiance of which is key to fighting guerrillas.

Even in lesser ground operations against small, weak foes, the U.S. military has not performed all that well. Although successful, the invasions of Grenada and Panama exhibited embarrassing snafus, such as friendly fire casualties caused by the inability of U.S. services to adequately communicate and coordinate and the wanton destruction of civilian areas and excessive casualties in what was supposed to have been a surgical operation, respectively. The hostage rescue mission conducted in Iran in 1980 had to be aborted. Finally, U.S. interventions in Lebanon and Somalia under the Reagan and Clinton administrations, respectively, led to ignominious cutting and running from those countries after successful enemy attacks – inspiring Osama bin Laden to believe he could compel U.S. withdrawal from overseas interventions by launching terrorist attacks against U.S. military forces (the U.S.S. Cole) and facilities overseas and even American territory.

Whenever the U.S. military has a setback, it usually hints around that the civilian leadership of the country was more to blame. And civilian leaders are partly to blame in most of these instances, but the military should not escape public scrutiny for these disasters – which it largely has. The problem is that the American public feels guilty for the alleged abuse of returning Vietnam-era veterans and for the fact with an all-volunteer Army, the average citizen doesn’t need to sacrifice much during all these American military adventures overseas.

Of course, if the public really wanted to do something to support American service personnel, it should put a stop to them fighting and dying in faraway developing nations to allegedly combat much exaggerated threats to the United States. However, sufficient public outrage needed to end the conflicts was not evident for either the Afghanistan or Iraq wars.

But what exactly went wrong in Afghanistan? As in Vietnam and Iraq, the U.S. military has not been fighting conventional armies, such as Iraqi forces during Desert Storm, which it is best at. Instead, in all three places, it was conducting what amounts to military social work. U.S. armed forces are fighting guerrillas that melt back into an all-important supportive indigenous civilian population. In Vietnam, initially, U.S. forces used excessive firepower, which alienated civilians; in Afghanistan and Iraq, the U.S. military, forgetting the lessons of Vietnam, did the same thing.

But American citizens ask, "Aren’t our forces more benevolent than the brutal Taliban? Why does the Taliban still get so much support in Afghanistan?" The answer: because they are Afghans. As my book, The Failure of Counterinsurgency: Why Hearts and Minds Are Seldom Won, notes, when fighting indigenous insurgents, the foreign invader never gets the benefit of the doubt. This central point makes it difficult for great powers to win wars against insurgents, no matter how nice they try to be to the civilian populace. And the U.S. military is usually fairly unfamiliar with the language and culture of distant lands of intervention, thus making it difficult to get good information about who is a guerrilla and who is not. Often the only way to win a counterinsurgency is to annihilate the entire country with indiscriminate and potent violence; yet the Soviets used such scorched earth policies in Afghanistan and didn’t win. Furthermore, the U.S. military would have difficulty selling such a morally bankrupt policy, which amounts to "destroying a country in order to save it," in a republic.

America is exceptional, however in a way the nation’s founders realized but has long been forgotten. Being far away from the centers of world conflict, the United States has probably the best intrinsic security of any great power in world history. Thus, the founders had the luxury of being suspicious of standing armies in a republic. Furthermore, as in any other public bureaucracy, when people are spending other people’s money, things often go awry. Thus, sending the military to war should only be done in the most dire cases of national security. Military restraint was the founders’ vision, but we have drifted far from it into a militaristic society in constant war.