Earlier this summer, The New York Times reported, Barack Obama gathered a group of historians for dinner at the White House. The president expressed concern that Afghanistan could hijack his presidency just as Vietnam overtook the stewardship of Lyndon B. Johnson. LBJ pursued a grand domestic agenda - civil rights and the Great Society - yet failure in Vietnam defined his presidency. Military analyst Harry G. Summers identified two reasons why the US abandoned the fight in Vietnam: 1. There was no society-wide commitment to victory. American leaders had not psychologically mobilized the home front behind the war, refusing to ask Congress for a declaration of war; 2. The US failed to go after North Vietnam for most of the war, focusing instead on its Viet Cong proxies. These fundamental errors are being repeated in the struggle against Islamist extremism. People in Europe and America do not grasp why their troops are fighting in Afghanistan. On Iran, Western leaders have not only avoided a head-on confrontation with the mullahs, but are even seeking to appease their Hizbullah and Hamas proxies. In fairness, Obama has tried to explain that Afghanistan is not a war of choice, but of necessity. "Those who attacked America on 9/11 are plotting to do so again. If left unchecked, the Taliban insurgency will mean an even larger safe haven from which al-Qaida would plot to kill more Americans." In fact, the situation in Afghanistan is muddled. The surviving Arab terrorists responsible for 9/11 - including Ayman Zawahiri and Osama bin Laden - have found refuge inside Pakistan. The Taliban are actually a loose confederation of religious fanatics (whose leader, Mullah Omar, also survives), Pashtun xenophobes, drug lords and tribal chiefs. The war is being waged on both sides of the Afghan-Pakistan border, and Pakistan has its own Taliban. In this context, Afghan election results - due today - are unlikely to herald a new dawn. The war is not going well. So America has revised its strategy. The focus is not on killing the enemy, but on avoiding civilian casualties while creating conditions necessary for society-building. Unfortunately, there are insufficient troops on the ground to accomplish this goal. Most of the country is too unsafe for aid agency personnel to operate. Washington has invested $30 billion in Afghanistan since 9/11 and now has 57,000 military personnel on the ground. Britain has committed to 9,000. In theory, there are 42 nations in the anti-Taliban coalition, but whereas the US has suffered 796 combat deaths and Britain 206, the combined loses of Germany, France and Spain amount to 87. No wonder support for the war in Britain is stagnating at 46 percent, while fully 65% of Americans expect the US will eventually have to withdraw without achieving its goals. BRITAIN'S unconscionable release on humanitarian grounds of terminally ill Abdel Baset al-Megrahi, the only person convicted in the December 21, 1988, Lockerbie bombing, could pave the way for billions of dollars in oil contracts between Tripoli and London. But what message does the Brown government's decision to play footsie with Muammar Gaddafi - while hiding behind the Scottish justice secretary - send to Britons already feeling cynical about staying the course in Afghanistan? This sordid episode, moreover, does nothing to illuminate who really blew Pan Am flight 103 out of the sky. In 2000, a man named Ahmad Behbahani, claiming to be a defecting Iranian intelligence operative, told CBS's 60 Minutes that Iran was behind Lockerbie; and that the motive for the attack was retaliation for the accidental downing in July 1988 of Iran Air flight 655 by the USS Vincennes, killing all 290 passengers. Behbahani spoke of an operation involving the Syrian-based Popular Front for the Liberation of Palestine-General Command and a group of Libyans trained and funded by Iran. If patience is running thin on Afghanistan, and there is no stomach to stop Iran, the reasons are obvious. From Lockerbie to Afghanistan, Western decision-makers have compartmentalized Islamist violence - rather than defined it as a strategic menace to the Western values of tolerance and liberty. The lesson of Vietnam is that wars become unwinnable when leaders fail to identify their true enemies, leaving their societies unmobilized, confused and lacking in motivation.