The U.S. counterterrorism campaign has both successes and failures, said three Columbia University political scientists in an interview with Xinhua on Thursday, ahead of the upcoming 10th anniversary of the 9/11 terrorist attacks.

On the upside, "U.S. efforts have been successful to the extent that there have been no major successful terrorist attacks in United States," said Professor Robert Shapiro, specialist in American politics and former head of Political Science department.

"Al-Qaeda has been on the defensive and has appeared to lose strength in Afghanistan, Iraq, and Pakistan," he elaborated.

"We are gaining some ground in the technology and organization to deal with the violence," added Professor Doug Chalmers, Professor Emeritus of Political Science and former dean of Columbia's School of International and Public Affairs.

Indeed, "the police/micro campaign appears to have been quite effective -- drone strikes, covert action and police/intelligence cooperation has significantly degraded Al-Qaeda and its affiliates, " said Professor Michael Doyle, Harold Brown Professor of U.S. Foreign and Security Policy and chairperson of the United Nations Democracy Fund.

But on the downside, "the military/macro campaign in places such as Iraq seemed to have generated more rather than less terrorism," continued Doyle, and "civil liberties have been put at risk... mostly unnecessarily."

On top of that, the U.S. hasn't "done well in dealing with the politics," said Chalmers.

In fact, Chalmers believes that "invading Afghanistan was a terrible mistake," as it made "the problem of dealing with the political side of terrorism much worse.""Obama was confronted by a tragically mistaken policy and is doing as well as anyone could with extracting the U.S., but that's only part of the problem," he continued.

But for Doyle, the war in Afghanistan was "necessary," even as it had been "neglected and bungled for eight years.""Current strategy -- focused against Al-Qaeda/Taliban, negotiating where possible, building Afghan security and then withdrawing -- seems a reasonable mix," he added.

However, even as such, Doyle is unsure about its success. " Whether it will succeed in stabilizing a legitimate Afghan government is unknown,"he added.