Gen. Stanley McChrystal says he is not discouraged by estimates that there are many more al Qaeda fighters in Yemen than there are in Afghanistan where he is overseeing a major surge in U.S. troops.
McChrystal, America's top general in Afghanistan, was reacting to a question from ABC's "World News" anchor Diane Sawyer who cited intelligence estimates that there are only 100 al Qaeda fighters in Afghanistan while there are as many as 300 in Yemen.
"I don't think that this war's in the wrong place," McChrystal said in his exclusive interview with Sawyer. "I think that the Afghan people both need and deserve this assistance."
McChrystal said al Qaeda, which launched the 9/11 attacks from its Afghan bases in 2001, has demonstrated it intends to "try to come back in to Afghanistan if in fact there is that opportunity with a Taliban regime or ungoverned basis. I think it's incredibly important. I think the president laid that out pretty clearly."
Watch Diane Sawyer's full interview with Gen. Stanley McChrystal as Sawyer anchors "World News" from Kabul tonight at 6:30 p.m. ET.
The most recent terror attacks on the U.S. have originated in Yemen, including the bungled "underwear bombing" of a Northwest jetliner over Detroit on Christmas day.
Nevertheless, President Obama stated over the weekend that he has no intention of sending U.S. troops to Yemen or to Somalia, another lawless country where al Qaeda is trying to establish bases.
McChrystal had argued to Obama last year that without a quick infusion of U.S. troops the chances of a victory in Afghanistan would be lost. Obama authorized 30,000 troops and the flow of fresh forces is just underway, but McChrystal said it has already blunted Taliban momentum and is turning the tide against the insurgents.
The general said he believes he is making good on his promise of a "quantum shift" on the battlefield.
Gen. McChrystal Says Optimism Taking Hold in Afghanistan
"I believe we're doing that now. I believe that we have changed the way we operate in Afghanistan. We changed some of our structures and I believe that we are on the way to convincing the Afghan people that we are here to protect them," he told Sawyer.
"We've been at this for about seven months now and I believe we've made progress. It's not a completed mission yet," he said.
McChrystal cited as evidence a meeting he recently held in a river valley in Helmand province, an area where the Taliban has been strong and was one of the first targets of the American offensive.
"When I sit in an area that the Taliban controlled only seven months ago and now you meet with a shura of elders and they describe with considerable optimism the future, you sense the tide is turning," he said.
The bulk of the surge forces won't arrive in Afghanistan until the end of this summer. When all of the troops are deployed, the number of U.S. soldiers in Afghanistan will be close to 98,000.
He suggested that the Taliban is feeling the pressure and some elements of the insurgency are willing to consider an end to their attacks and negotiate with the government of President Hamid Karzai.
"I can't speak for [Taliban leader] Mullah Omar. He's indicated no willingness, but I can certainly say that within his organization there are constant reverberations of interest in doing that," McChrystal said.
The general said he sends Obama regular updates through the military chain of command, but has little personal contact with his commander-in-chief.
"We don't have personal conversations. We haven't recently, but we just been through the Christmas holidays, so I feel pretty comfortable the way we are," he said.
The general said he is convinced that the Afghan fight can be won, and only one thing could shake that conviction.
"I think that it would be a belief that the Afghan people have lost faith, that the future can be better and that we can help them get there. If they were to reach that point, then I think that I would sense that this would not be possible. I don't feel that now."
Afghan Poll Shows Shift of Approval
Despite signs of progress, the fight for Afghanistan appeared to be becoming more deadly as U.S. and NATO troops heightened their presence and increased their patrols.
Three American and three NATO soldiers died today in ambushes and roadside bombs. The latest casualties brought to 10 the number of Americans who have died so far this month, making it a bloody start to a new year of combat.
Another alarming trend is that civilian fatalities in Afghanistan rose significantly in 2009 for the second straight year, according to United Nations numbers obtained by ABC News, mostly because of growing Taliban violence rather than U.S. and coalition mistakes.
The U.N. said 2,412 civilians died in 2009, an increase of 14 percent over the prior year and nearly 60 percent over 2007.
That massive spike over the past two years reflects the mounting violence in Afghanistan that has left large pockets of the southern and eastern parts of the country virtually controlled by insurgents.
But the numbers are a success for McChrystal, who has made reducing the number of civilians killed by U.S. forces one of his top priorities.
In 2007, 41 percent of civilian fatalities were caused by the coalition. In 2008, that dropped slightly, to 39 percent. And in 2009, that percentage dropped significantly, down to 25 percent, according to the United Nations numbers.
The general's optimism comes as a new poll shows that Afghan are also believing that improvements are on the way.
The survey by ABC News, the BBC and ARD German TV found that 70 percent, a 30-point advance in views, that the country is headed in the right direction. That is the highest level of optimism since 2005.
Afghans' expectations that their own lives will be better a year from now have jumped by 20 points, to 71 percent, a new high. And there's been a 14-point rise in expectations that the next generation will have a better life, to 61 percent.
ABC News' Nick Schifrin contributed to this report