Second, the expanding U.S.-led nation-building mission in Afghanistan is fueling the Taliban resurgence. Opponents of a surge argue that 40,000 more American troops would make the Afghan people regard the U.S. as a foreign occupier. Trouble is, they already do and have for eight years.
Third, there is a misperception among U.S. policy elites that a troop surge increased stability in Iraq. Instead, paying off now-restless Sunni adversaries to quit fighting American forces has bought what probably will be only a temporary respite from the violence. It ain't over till it's over.
Fourth, ultimately, in a republic, escalating an unpopular war is usually political suicide for politicians and ultimately for the war effort. If the public and Congress are balking at sending a measly 40,000 additional troops, they will never be willing to send the much larger number of troops needed to actually win.
Fifth, throughout history, many great powers have either lost to a lesser foe or won only with great difficulty, because they did not commit enough forces from the start. The invader must do so or give up and get out. For example, in the late 1700s, the British lost the American Revolution because they did not have sufficient forces in a large territory. In the early 1800s, Napoleon lost against the British and Spanish guerrillas, because he failed to commit the effort needed to win. During the same period, the Ottoman Empire and its surrogate, Egyptian Muhammad Ali, finally marshaled enough troops struggling to overcome Wahhabi guerrillas in Arabia. The British — in the Anglo-Sudan War in the late 1800s and the Boer War around the turn of the 20th century — didn't initially send enough forces to win but then later sent more and won "ugly." In Vietnam, the United States gradually escalated to more than a half million troops, but this was not enough to beat a North Vietnamese/Viet Cong force of only 100,000.
The bad news is that Vietnam was a much smaller country — in both population and area — than Afghanistan. Even the Army's new field manual on guerrilla warfare says that 20 to 25 occupation forces are needed per one thousand inhabitants.
Frank Rich of the New York Times estimates the Afghan population at 32 million, which would necessitate an occupying force of 640,000 to 800,000 in order to have a good chance of winning. If we send an additional 40,00 to join the 68,000 U.S. troops there, along with the 30,000 (mostly ineffectual) European troops, this amounts only to a paltry 140,000.
After eight long years of a lackadaisical effort, another 40,000 this late in the game won't change the fact that the Obama administration's effort remains half-hearted. Instead, the U.S. should cut its losses, withdraw from Afghanistan, and concentrate on pressuring al Qaeda in Pakistan. Reducing our military footprint will ensure that we neutralize more anti-U.S. Islamists than we provoke.
Ivan Eland is a senior fellow at the Independent Institute.