ABC News March 16, 2019

Taliban peace talks reignite debate over whether US is negotiating with 'terrorists'

WATCH: Across the Pond: New violence in the Middle East

After nearly 18 years of war, the U.S. and the Taliban are deeply engaged in what was once unthinkable: peace talks.

The militant group has killed countless American soldiers and even more Afghan troops and civilians. It’s been bombed and blown up by U.S. weaponry, pushed out of control and from the capital, Kabul, only to fight its way back toward power year after year.

And yet, American diplomats now find themselves on the other side of the table, without Afghan government representatives, to negotiate an agreement that will see U.S. troops withdraw from Afghanistan.

The United States has a longstanding policy of not negotiating with terrorists.

However, a key part of the Trump administration's decision to engage the Taliban directly stems from the Afghan group not being on the State Department's list of "foreign terrorist organizations," or FTOs.

That’s a legal designation made by the U.S. government that allows it to bring penalties -- financial sanctions, visa restrictions, prosecution of individual supporters -- against a group. The department has a long list of FTOs, from groups like the Basque separatists in Spain and the Tamil Tigers in Sri Lanka, to more well-known names like al Qaeda, ISIS and Hezbollah.

Yuri Gripas/Reuters
Secretary of State Mike Pompeo speaks during a news conference at the State Department in Washington, March 15, 2019.

While the Taliban’s Pakistan-based branch was designated as an FTO in 2010, the Taliban itself has never been.

The group likely does meet the criteria: It is foreign-based, actively engaged in terrorist activity and that activity is a threat to U.S. national security interests. With the Taliban, the label should be a “no brainer,” as one U.S. official told ABC News.

This is also complicated by the fact that senior U.S. officials occasionally refer to them as terrorists, despite lacking the legal designation. On March 4, for example, Secretary of State Mike Pompeo said the U.S. was “trying to negotiate with the Taliban terrorists in Afghanistan.”

When asked about the discrepancy, a State Department spokesperson pointed to the Taliban’s listing as a Treasury Department “specially designated global terrorist” entity since 2002. That separate designation means it and its members are subject to sanctions, embargoes and, because of an act of Congress in 2008, other things like immigration restrictions.

(MORE: Taliban and senior Afghan politicians hold talks in Moscow, upsetting government)

Because of that, the U.S. has “full power to pursue the Taliban’s financial and other activities,” the spokesperson said.

Still, the State Department designation is a special status.

AFP/Getty Images, FILE
Afghanistan's National Security Adviser Hamdullah Mohib attends a press conference closing a two-day United Nations Conference on Afghanistan in Geneva, Nov. 28, 2018.

“It really makes for a lot of confusion when you have a group that’s been as deadly as the Taliban, who provided sanctuary for al Qaeda to stage its 9/11 attacks, that it had never been added to the FTO list. ... That’s incredibly problematic,” said Jason Blazakis, who served as the director of the State Department’s Counterterrorism Finance and Designations Office from 2008 to 2018.

(MORE: Trump's claims of US success in Afghanistan ring hollow amid Taliban talks, reality on ground)

The inconsistency is largely for political reasons -- a long-running fear during the Bush, Obama and now Trump administrations that labeling the group a foreign terrorist organization would anger and alienate them, making it harder for U.S. diplomats to ultimately engage them in any political process.

To successive administrations, the “timing” was never right to make a designation.

But there are no legal restrictions on American officials talking to terrorist organizations or their leadership. In Colombia, for example, the U.S. and the allied government engaged with the Revolutionary Armed Forces of Colombia—People's Army (FARC), even though they have been designated a terror group since 1997.

(MORE: US envoy defends Taliban peace talks, Trump says deal means Afghanistan withdrawal)

Some analysts say designating the Taliban a terrorist organization would have given U.S. negotiators something to concede in talks in exchange for Taliban promises.

Wakil Kohsar/AFP/Getty Images, FILE
Afghan security personnel stand at the scene of a suicide attack by Taliban militants on the Afghan parliament building in Kabul on June 22, 2015.

“You could have removed the FTO tag as part of this process, as something you would ‘give’ the Taliban,” said Blazakis, now the director of the Middlebury Institute’s Center on Terrorism, Extremism, and Counterterrorism. “Now it’s a missing potential incentive.”

Perhaps even more importantly, “terrorist” is a label that matters to the U.S.-backed Afghan government.

“The Taliban and terrorism -- it’s one DNA,” Afghan National Security Adviser Hamdullah Mohib said Wednesday in Washington, condemning it as “a group that murders civilians in cold blood, conducts terrorist activities across the country and blows up schools and mosques.”

(MORE: US, Afghan government tensions burst into public over Taliban talks)

The Afghan government has been increasingly frustrated by U.S. talks with the Taliban for that reason -- the administration has excluded the Afghan government while dealing directly with this “terrorist” organization.

“It would be a shame if a deal was made with the terrorists who killed more than 5,400 Americans, and if they were given control of the lives of the Afghan people. That would be a win for those terrorists,” Mohib said Tuesday.

Tensions between the U.S. and Afghan governments over the Taliban talks burst into public this week, but for now, the U.S. remains on track with its negotiations with the militant group.