General John Allen, the top commander of U.S. and NATO forces in Afghanistan, is no quitter.
In dramatic testimony before the House Armed Services Committee on Tuesday he made the case for the U.S. to “stay the course in Afghanistan.” He stressed the commitment and sacrifice of his troops to ensure that Afghanistan will no longer be a safe haven for terrorists and Taliban oppressors.

But there was one problem.

The general failed to realize that at home, on the battlefield of U.S. public opinion, his brave words are only making people shake their heads with regret.

The American people, Congress and the White House have already concluded that even if hundreds of thousands of U.S. troops remain in Afghanistan indefinitely, they will never build Afghanistan into a safe, reliable and secure ally.

Our Afghan partners are corrupt, increasingly unreliable and some of them appear to be in league with the Taliban and the terrorists we are supposed to be fighting against. Pakistan continues to support and encourage the very forces that are keeping Afghanistan destabilized.

A March 13th poll from USA Today/Gallup found that 50 percent of Americans want the U.S. to speed up its withdrawal from Afghanistan. Twenty-four percent of Americans want the U.S. to stick to President Obama’s timetable for withdrawing the troops by 2014. Only 21 percent say they want the U.S. to stay in Afghanistan as long as it takes.

These findings complement those of another recent poll from the Pew Research Center which found that 57 percent want to bring the troops home as soon as possible and only 35 percent want them to stay until the country is stabilized.

Even Republicans, who typically take the lead in supporting military efforts, are tired of this war.

A recent poll from ABC News/Washington Post shows Republican support for the war dropping to 47 percent. This is down from 74 percent GOP support back in 2009.

Even conservative stalwarts like Ann Coulter and Grover Norquist have called for the U.S. to rethink its continued presence in Afghanistan.

All of the remaining GOP presidential candidates – Mitt Romney, Rick Santorum, Newt Gingrich and Ron Paul – have all said that the U.S. should leave Afghanistan in the near future though they differ on the swiftness and conditions of such a withdrawal.

Decisions about national security should not be decided solely on the basis of election-year politics and public opinion. The people doing the fighting deserve the nation’s respect for their on-the-ground perspective.

But with Afghanistan, we have a case where public opinion is driving politicians to salute the military for all they have done and tell them it is time to come home.

Nation building is not going to work in Afghanistan.

The violence in that country over the past few weeks has only added to the American people’s war weariness and prompted more calls to speed up the withdrawal of coalition forces.

They see violent protests against U.S. forces by Afghan civilians. Back home, the American public also sees increased “green on blue” violence where Afghan soldiers have attacked the very coalition troops that are training and arming the Afghans.

And earlier this month, a U.S. soldier allegedly went door to door in an Afghan village and killed sixteen Afghan civilians before burning some of the bodies.

After 10 ½ years and over 1,780 U.S. casualties, public opposition to the war is a threat to undermine respect for military leaders who insist on staying on a misguided path.

In an interview with a CBS affiliate in Pittsburgh, President Obama said of the incident, “It makes me more determined to make sure we are getting our troops home. It’s time. It’s been a decade. Frankly, now that we’ve gotten bin Laden, Now that we’ve weakened Al Qaeda. We are in a stronger position to transition than we would have been two or three years ago.”

Afghan President Hamid Karzai held a public meeting with relatives of the massacre victims last week where he declared “Let’s pray for God to rescue us from these two demons. There are two demons in our country now.”

Karzai was referring to the United States Military and the Taliban with that statement.

Choking back tears, he added “This has been going on for too long. You have heard me before. It is by all means the end of the rope here.”

Back in 2010, President Obama helped broker an agreement with NATO to remove most coalition forces from Afghanistan by 2014 and transition security responsibility to the Afghans.Don’t be surprised if President Obama reacts to these forces by announcing an accelerated timetable for withdrawal from Afghanistan.

Vice President Biden has proposed a small, special forces operation be left in place to prevent any terrorist activity from gaining a foothold there.

The American people would be right to make this demand of the commander in chief. And they just may do it.

Juan Williams is a writer, author and Fox News political analyst. His most recent book "Muzzled: The Assault On Honest Debate" (Crown/Random House) was released in 2011.