Americans are closely divided over whether the United States should send more troops to fight the war in Afghanistan, according to a new Rasmussen Reports national telephone survey.

Thirty-seven percent (37%) say yes to sending more troops, while 40% say no. Twenty-three percent (23%) are not sure.

Adults ages 18 to 39 are much more strongly opposed than their elders to sending more troops.

Perhaps most significantly for President Obama as he and his advisers try to decide how to proceed in Afghanistan, 54% of Democrats oppose sending more troops there. Fifty-three percent (53%) of GOP voters are in favor of sending in additional troops. For voters not affiliated with either party, it’s a much closer call.

Twenty percent (20%) of U.S. voters say all American troops should be brought home from Afghanistan immediately. Another 17% oppose an immediate withdrawal of U.S. forces but believe a firm timetable should be established to bring all troops home within a year. Democrats are much more strongly in favor of pulling out the troops.

But just 33% of all voters believe it is even somewhat likely that U.S. combat troops will be removed from that country by the end of the president’s first term.

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Two-out-of-three Americans (66%) are now at least somewhat concerned that the war in Afghanistan will become another Vietnam for the United States. Thirty-eight percent (38%) are very concerned.

Just 25% of adults are not concerned – 19% not very concerned and six percent (6%) not at all concerned.

This marks a high level of concern since, even by August 2007, Americans were almost evenly divided over whether the war in Iraq was like Vietnam for the United States. Forty-seven percent (47%) said Iraq was like Vietnam. Forty-four percent (44%) disagreed and say it was not.

President Bush invaded Afghanistan because the country’s radical Islamic Taliban government was giving safe haven to the terrorist group al-Qaeda and its leader Osama bin Laden, the mastermind of the 9/11 attacks on America. Sixty-nine percent (69%) of Americans say it is very likely that al-Qaeda will be back in Afghanistan if the country is taken over again by the Taliban. Another 12% say it is somewhat likely. Just four percent (4%) say it’s not very likely.

Seventy-six percent (76%) say it is important for the United States to capture or kill bin Laden. Fifty-one percent (51%) believe it is very important. Sixteen percent (16%) say it’s not very or not at all important.

Still, 38% of adults think Pakistan’s stability is more important to U.S. national security than the stability of Afghanistan. Only 24% put Afghanistan’s stability first, and another 39% are not sure which is more important.

Fifty-five percent (55%) of voters now expect the war in Afghanistan to get worse during the next six months, a 14-point jump from a survey a month earlier. Confidence is also down in America's conduct of the War on Terror.

Eighty-seven percent (87%) of voters are at least somewhat concerned about the security of nuclear weapons in Pakistan as the Taliban continues to make gains in that country. Sixty percent (60%) are Very Concerned.

From a list of 18 nations regularly in the news, most Americans pick just five that they think the United States should defend militarily, and the five don’t include Pakistan and Afghanistan.

Earlier this month, 49% of Americans said that most of their fellow countrymen have already forgotten the impact of the September 11, 2001 terrorist attacks in which 3,000 died.

Only 12% of voters continue to believe that the United States should be the world’s policeman.

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