In January 1842, a British column of 4,500 soldiers and 16,000 civilians, including women and children of the soldiers' families, sought to leave Afghanistan for British India through snowy mountain passes, where they were repeatedly ambushed by Afghan guerrillas. In the end, only one survivor, Dr. William Brydon, escaped. The British tried again to conquer Afghanistan in 1878-80 but finally gave up in 1919.

In February 1989, the Soviet Union retreated from Afghanistan after having deployed 620,000 soldiers there over 10 years, on average about 100,000 at a time. Of that total, 14,450 were killed in action or died of other causes while 469,685 were wounded or fell ill. The strain on the Soviet economy and armed forces was among the causes of the collapse of the Soviet Union in 1991.

Today, the U.S. is plunging into a full-scale war in Afghanistan not unlike the British and Russians earlier. The war in Afghanistan, literally halfway around the world from the U.S., has become President Obama's war just as Iraq was President George W. Bush's war. And it promises to be equally contentious.

The president set the course three months ago when he noted that the U.S. had deployed to Afghanistan to attack the al-Qaida terrorists and Taliban extremists shortly after 9/11. Now, he said: "What is our purpose in Afghanistan?" His answer: "If the Afghan government falls to the Taliban — or allows al-Qaida to go unchallenged — that country will again be a base for terrorists who want to kill as many of our people as they possibly can."

"We are in Afghanistan to confront a common enemy that threatens the United States, our friends and our allies, and the people of Afghanistan and Pakistan who have suffered the most at the hands of violent extremists," he said. The president asserted that he had "a clear and focused goal: To disrupt, dismantle and defeat al-Qaida in Pakistan and Afghanistan, and to prevent their return to either country."

So far, however, polls this month show the president has not aroused much public enthusiasm for the Afghan war. One poll said 50 percent of Americans favored the war while 48 percent opposed it. Another survey found that 66 percent considered the economy, jobs and government spending the nation's top priorities while only 9 percent thought the wars in Iraq and Afghanistan were necessary.

Even in the president's own party, skepticism abounds. During a hearing on Capitol Hill, Rep. Jim McGovern, a Massachusetts Democrat, contended that Obama's troop buildup in Afghanistan would only make it harder to withdraw from a war that lacks a "clearly defined mission." By this fall, the U.S. will have 68,000 troops in Afghanistan, with no exit promised or in sight.

Bloomberg News Service quoted McGovern: "I wish the current administration would do in Afghanistan what I asked the previous administration to do in Iraq: And that is to simply put forth a clearly defined policy, a clearly defined mission — it's not a radical idea. I am tired of wars with no exits, no deadlines and no end."

Active-duty and retired military officers have privately questioned whether the cost in blood and treasure, even in the relatively low level of fighting in Afghanistan so far, has served the national interest. As of last week, 708 American military people have been killed and 3,063 wounded there. The Center for Defense Information, a nongovernment research institute, estimates that Afghanistan has cost $440 billion since 2001.

With all of the issues confronting the U.S. today, one critic said: "Afghanistan is a fool's errand. It is a money pit. Most importantly, it is unworthy of our young warriors' lives as our vital security interests do not abide there."